Accidently mixed instant and cooked pudding packages

update: It seems that the salts used in instant pudding are heat stable (one turns into the other one at 450°C), so it's possible that it might work by following the cooked directions ... but I'd advise a slurry as a backup.

You're going to have to add something to fix it. Either more gelatin (to have it set cold), or starch to have it set when boiling.

I'd probably go with the hot method -- you'll bring it to a boil, which will screw up the setting properties of the gelatin. I suspect that you'll want to let it boil for a minute or so, to make sure the gelatin isn't going to set at all (and possibly make it too thick, or interfere with the starch).

You didn't say which size of boxed mix you're using, but looking at a few recipes, it seems like you want 3 to 4 TB of cornstarch to set 2 cups of milk. Use that as a basis to scale your recipe.

(updating instructions per DebbieM's comment)

So :

1. Mix cornstarch (1.5 to 2 TB per cup of milk needed for the instant pudding) with some (less than 1/4 c.) of milk in a jar, seal and shake to make a slurry.

2. Stir in the cold milk (the sum of what's called for on both boxes).

3. Heat to a boil (see notes from cooked pudding package about stirring, etc).
4. Check to see how well the pudding coats the back of a spoon. (wipe a finger through it to get an accurate estimate of how thick it is)
5. If not thick enough (note: it will thicken more when cooled), add some of the slurry, and let it boil for a minute or so (keep stirring or whisking during this).
6. Repeat 4 & 5 'til you've achieved the thickness desired.
7. Follow the cooked pudding package instructions from there.

If you don't have cornstarch, I've seen some recipes that use flour (about 1/4c. per 2 cups of milk), but they're always chocolate ... I suspect it's to cover up the raw flour taste.

If you have unflavored gelatin, you could also bloom some in some cold milk, and then mix it in with the cooked pudding as it's cooling to try to achieve the desired thickness, but too much might end up setting like a blancmange.

My annual holiday meal fail this year was : maxing instant and cook and serve pudding. I mixed the packages and prepared both as instant pudding. This was Wednesday at 11 pm. I debated to freak out, try making a new banana pudding pie with what I had left, or just wing it and stick it in the fridge... well I mentioned it was 11pm Wednesday? Yeah, so I opted out of an extra holiday melt down, stuck it in the fridge and hoped for the best. I decided not to chance messing up my entire day Thursday, I didn’t check the banana pudding until I served the rest of the desserts after dinner. I wanted to be just as surprised as everyone else if this thing was still in liquid form!

However, very much to my surprise, when I went to serve my banana pudding, “I’ll be damned, it’s pudding!”

So, when this happens to you less than 24 hours from holiday meal time: shrug your shoulders, stick it in the fridge, keep calm and holiday on!

I just did this exact same thing with Jello brand pudding and I just heated it in the microwave for 8 mins stirring every 2 mins ( as per cook and serve microwave directions) and it worked.

I did the same thing. Mixing up the cooked for instant. I just went ahead and used it uncooked and it set up fine and tasted delicious. Don’t sweat it because it works fine. Maybe a better flavor and texture to boot.