Preheat oven to 350°. In a large bowl, mix mayonnaise and mustard. Reserve scant 1/4 cup mayo mixture for topping. Add to large bowl, chicken, bacon, and cheese. Mix until well blended.
Open Crescent roll dough and spread on counter. Cut into 9 equal squares.
Place into muffin cups. Add 1 level cookie scoop of filling, about 2 tablespoons into center of each crescent square. Bake 15-20 minutes.
Remove from oven and cool 5-10 minutes. Top with lettuce and tomato. Place remaining mayo mixture in a baggie, snip a small hole in the corner and squeeze to top cup with extra flavor!
To freeze, place in muffin tins and freeze overnight. Remove from muffin tins and store in ziploc freezer bag in the freezer. When ready, place in muffin tin, no thawing required! Bake 20-30 minutes at 350° and top as usual.