How to make pumpkin extract

The pumpkin flavor you're likely looking for is nothing more than the spices that are added to pumpkin "stuff": cinnamon, nutmeg, cloves, etc. If you attempt to do an extract to achieve "pumpkin essence", you will not be happy with the results.

I have been a home brewer (beer, wine, mead, etc.) for 20+ years and have seen many attempts from various brewers to make a "pumpkin beer". Long story short (and you can do a search and verify what I'm saying on any beer brewing forum's out there), it's the spices that make the flavor, not the pumpkin squash fruit.

Bottom line is there is no "typical anticipated pumpkin flavor" imparted by just pumpkin. To make a great pumpkin beer, the guys who have made multiple batches of pumpkin beer using varied recipes (using chunked up pumpkin, cooked pumpkin, roasted pumpkin, etc.), all ended up finding the perfect pumpkin beer was made using only the spices and not even using any pumpkin at all.

This is speculation, since I have never done it, and I don't think it is practical or more effective than just cooking with pumpkin puree for these applications.

If I were to try this, I would:

1. Roast pumpkin (just the flesh, not the seeds or peel) to develop the roasty flavors. You would roast it dryer than you would for pureeing, maybe to a leathery texture, but not completely dry.
2. Infuse a very strong vodka or grain alcohol with the pureed roasted pumpkin for a week or six.
3. Filter the the liquid off with a coffee filter.
4. Optionally, reduce the the liquid extremely carefully (probably outside for safety reasons) until it becomes reasonably concentrated.

I suspect the results of this would be underwhelming. You will note that this is essentially how fruit liquors are made at home, except for step 1 (unique to pumpkin) and step 4.

For curiosity, see also this recipe for a pumpkin liqueur, although it also has many additional pumpkin flavors. The key difference is you won't use extra flavors, and you will use a much higher pumpkin to solvent ratio.

Perhaps you could do an alcohol extract, where you essentially let a product sit in a low flavor alcohol (like vodka) for a period of time. I've had success doing this at home with cinnamon sticks and vanilla beans, but some plants like mint don't do too well. spices seem to do best. maybe toasted pumpkin seeds ?

You could try using a whip cream dispenser. I know it sounds weird but it's actually used for this purpose with spices etc. Look up the manufacturer iSi and you should find some info on flavor extraction. If you just want the result (flavor), maybe not so much the adventure, search for "pumpkin extract". There are a few- King Arthur Flour is reasonable ($6). However, the other posts are correct, you will need the cinnamon, nutmeg, etc to achieve a 'pumpkin pie' flavor!! Another option is coffee flavor syrups, which are available everywhere and pretty good, in my opinion. If you have a friend, or niece, who works at Starbucks, you can surely get them to give you a coffee cup full of just syrup! When it's in season they have huge gallon jugs of it, which is not just the spices in syrup, but the pumpkin pie flavor in liquid form. Good luck!!