Preheat oven to 375°F. Spray 30 mini muffin cups. In large bowl, mix spinach, tomatoes, cream cheese, sour cream and taco seasoning mix; set aside.
Place Doritos in a small ziplock bag and seal. Finely crush the chips to measure 1/2 cup. Stir crushed chips into the spinach filling.
Separate 1 can of dough into 10 biscuits; separate each biscuit into 3 layers. Sometimes you can only separate them into 2 and that is totally fine. Just take that into account that you're one less mexican cup. Place 1 layer in each muffin cups and press dough on bottom and up side of each cup.
Fill each cup with about 1 Tbsp spinach mixture. Sprinkle filling in each cup with about 1 tsp cheese. Bake 10 to 12 minutes or until edges of biscuits are golden brown. Cool in pan 5 minutes; remove from pan to cooling rack.
Optional: Add 1 cup of cooked shredded chicken, cooked ground beef, or ground turkey