Mix the coriander, dry mustard, salt, pepper, and garlic powder in a small bowl; rub the mixture over the thighs, coating them evenly and thoroughly. (IF POSSIBLE - do this ahead of time and set them covered in the refrigerator for up to 8 hours. It's not absolutely necessary, but it really amplifies the spices!)
Pour the beer into a 6-quart Instant Pot (electric pressure cooker); nestle the thighs into the beer.
Lock the lid onto the pot.
Set the machine to cook at high pressure for 45 minutes by hitting Manual and adjusting the time setting. (My Instant Pot has a "manual" setting so I just used this.)
Once 45 minutes is up, use the quick-release method to drop the pot’s pressure to normal.
Unlock and open the cooker. Transfer the thighs to a carving board; cool for a few minutes. Debone the meat and chop it into small bits.
Set the Instant Pot to its "saute" function; bring the liquid inside to a simmer.
Cook until reduced to about half its volume when you opened the pot in the previous step, about 4-6 minutes.
Stir in the brown sugar, vinegar, mustard, and tomato paste until smooth. Cook for 1-2 minutes, stirring all the while.
Add the chopped turkey, stir well, and set aside unplugged for a couple of minutes to heat through.
Serve on buns with a side of garden veggies and/or cole slaw!