How to add a salty/bacon flavor and texture to vegan collard greens?

As a vegetarian, I regularly try to compensate for the lack of meat in a normally meat-containing dish using a number of methods, though I feel none can truly replace the addition of meat perfectly. In my experience, duplicating the effects of the addition of meat to a dish requires considering individually the effects the addition would have.

First I'll address the fat added. Since the lard present in bacon is high in saturated fats, you can attempt to duplicate that using vegetable oils that are high in saturated fats, like hard margarine or palm oil. While I wouldn't normally advocate with using an oil specifically because it has higher saturated fat content (for health reasons), in this case it will likely help the quality of the finished greens. Consider using a smaller proportion of the more saturated fats by adding in a lighter/healthier oil, like canola or grapeseed, as a portion of the added fat. There is no single rule for getting the fat content of a dish like this right, and it's often a matter of taste.

The smokiness added by the bacon is also a consideration. While liquid smoke could work, the volatility of the product can contribute to the flavor getting poorly concentrated in the food. I have had good results with both smoked salt and smoked black pepper in concentrating smokiness in a dish, and I have found that adding either more near the end of cooking encourages the flavor to be retained more prominently.

For the savoriness added by the aminos in the pork, there is a wide variety of vegan options for its substitution. A good place to start, in my opinion, is to use a vegan not-meat bouillon (e.g. from Edward & Sons) as the base of the broth. The addition of nutritive yeast (and to a lesser extent mushrooms) can also help infuse the broth with umami, and is a common ingredient in vegan broth preparations. If desired, the addition of liquid aminos (e.g. Bragg's Liquid Aminos), and/or MSG can help further improve the savoriness of the greens.

For the texture added by the bacon itself your intuition of using TVP or vegan bacon is likely the way to go. While neither adds much flavor itself (vegan bacon being far more mellow in its baconiness), they are probably your best bet for duplicating a meaty texture.

Most of the varieties of a product called Bacon Salt (originally semi-local to my area, but I think now available nationally in the US and online) are vegan, and all, to my knowledge, are vegetarian.

I've used it in concert with various fats (olive oil, butter, neutral vegetable oils) to get fairly convincing result, usually adding it directly to the fat a short time before adding the greens if I'm using a slow braising green like collard greens. Just make sure you don't get the oil so hot that it burns the Bacon Salt. It does a nice job of infusing the smoky flavor into the oil that way.

Alternatively, you could go a different direction entirely and reset your expectations: I'm very fond of various Ethiopian preparations of collard greens, sometimes written as "Abesha Gomen", which may or may not use butter depending on the variation, but does use various spices. There are fairly reasonable recipes for that online if you search for either Abesha Gomen or Ethiopian Collard Greens.

The normal approach we have tried has been salty, smokey, sweet. Salty and smokey has been done with smoked and kosher salts. the smokiness is aided by the addition best of not just a liquid smoke product, but earthy things like toasted sesame oil. A freshly ground shiitake powder can also be added.

The sweet is generally managed by adding maple syrup. This we normally cut with liquid aminos or vegan Worcester sauce and onion powder and nutritional yeast (less the latter, my partner dislikes it).

The most important technique element to apply would be to cook the tempeh strips, or whatever you're preparing, very low and very slow for at least thirty minutes. We typically use a cast iron skillet for the task as the reduction will continue needing attention. (obviously, add the greens after the tempeh or mushrooms are done cooking). You can also marinade and dehydrate portabella.

Dried mushrooms are bound to work best for a crisp texture, and will likely provide a better counter to the greens than mushy tempeh (which are well suited to A tofu scramble). We have generally been disappointed by both pre-packaged vegan bacon substitutes as well as any TVP 'bits' approaches as the first doesn't cook up or modify well to achieve flavor, and the latter just don't hold up at all. The fatty lip and mouth feel will be boosted by adding a final bit of toasted sesame and a better amount of a mild oil at the end.

Coconut oil. As OmniaFacial mentioned about solid fats, a good tasting raw coconut carries all the the spices well and softens up the collards brillantly.

Dried onion is also somehow more compatible than fresh with collards, IMHO.

Secret weapons: coiander seed or root and either a bit of yeast extract instead of soy sauce or Braggs (very high umami); or a few drops dark sesame oil with tiny bit prickly ash oil and a dribble of black vinegar for an Asian Fusian kick.

I really like how this web page at the inimitable herbivoracious.com describes the spirit of experimentation that lead to his version of a "vegan bacon" - in short, the flavor comes from the salt and sugar that some others have already mentioned, and smoked paprika. I was sufficiently intrigued that (as a "true bacon" eater) I tried it out over a salad last Christmas and I can wholeheartedly recommend it. The flavor is awesome - pretty close to bacon but it definitely has some awesomeness that's all its own. Texture is spot on, too.

Toasted pumpkin seeds are to my mind the perfect solution + a bit of salt, paprika. You'll have a very similar crispy, caramelized fat taste that makes bacon so tasty.

Try J&D foods bacon salt...its vegan! Bacon Salt

You might look into a product called Vegan Magic Bacon Grease. It is a seasoned coconut oil product, intended to replace bacon grease as an ingredient - so it has sweet, salty, and smoky flavors. One of the uses mentioned on the website is frying greens southern style, like collard greens, so it seems like it might work to add some of the flavor you're looking for (instead of or in addition to any vegan bacon, depending on your recipe, I'm not really familiar).

I can't say if it tastes like bacon, been too long without, but it does taste pretty good, I recall.

Additionally, if you wanted to include pieces of veg bacon for texture and not just the fats and flavors, let me add a suggestion for another product, Hickory and Sage Smoked Seitan by Sweet Earth (also sometimes called benevolent bacon), as it is one of the best bacon alternatives I've seen, it has a lot of flavor and is pretty good for adding into recipes (I've used in soups, etc, for flavor and texture). Again, not sure if it tastes like bacon (I'm actually inclined to think "no", it's an alternative not a replacement) but it tastes really good and packs a lot of flavor.

Maybe, roast 1 pack med sliced fungi in 1/4ctamari, 1T maple, 1T liquid smoke, 2t natural oil in a coverd pan 400 25-30mins, til they've released their juices, then uncovered til they've sucked them almost all the way back up, then toss them in your 3/4 of the way cooked greens?