Cut puff pastry into 2-3" squares/rectangles. You should get 12-16 pieces per sheet.
Spray your muffin pan and place one of the puff squares in each spot.
Spoon in about 1 tablespoon of pumpkin spread.
Cut each of the brie bites in quarters and place one in each of the muffins.
Sprinkle with thyme (fresh or dried) and chopped nuts.