Place 1 cup pecans into NF Hot Cold Blender or food processor. Pulse 2-3 times to chop up the pecans.
Add in the salt, brown sugar, flour, and sliced cold butter. Pulse 4-5 times until the the mixture is combined and the butter is in little pebbles. Set aside for later.
Mashed Sweet Potatoes
Add 1 cup of water to the inner pot of the Ninja Foodi. Place the sweet potatoes on the rack in the low position. Put the pressure lid on and turn the valve to seal. Pressure cook on high for 2 minutes. Immediately release the pressure. Remove the rack and let the potatoes cool so you can handle them.
Peel the skin off of the sweet potatoes using a spoon or a vegetable peeler and cut the ends off.
Slice the sweet potatoes into ½-1" slices.
Pour ½ cup of chicken bone broth or stock and ½ cup of orange juice into the inner pot. Put the sliced sweet potatoes in the inner pot directly in the liquid. Put the pressure lid on and turn the valve to seal. Pressure cook on high for 10 minutes. Immediately release the pressure.
Add in the salt, red pepper flakes, honey, balsamic vinegar, and butter. Mash them in the pot with a utensil that is safe for non-stick. Or you can transfer to a bowl, then add in your ingredients for mashing and mash with a hand mixture. I use the Mix 'N Mash from Pampered Chef and it works great. Mash your sweet potatoes to the consistency you like. Taste and season to your liking.
Transfer the mashed sweet potatoes into your casserole dish. Preheat the Ninja Foodi on bake/roast at 350° F for 10 minutes.
Spread the topping over the top of the sweet potatoes. Place your casserole dish on the rack or use a silicone sling and put it into the Ninja Foodi. Bake at 350° F for 20 minutes. Check on the sweet potatoes at 10 minutes and brush on ¼ cup of melted butter if desired. Continue to bake for the remaining 10 minutes. The top should be nice and brown, but not burnt. Allow to cool for a few minutes.