Preheat oven to 400F and spray a 12-muffin tin or silicone mold with nonstick spray.
Cook the ground beef over medium-high heat until no pink remains. Use a spatula to finely crumble the beef as it cooks. Towards the end of cooking, add the spices and stir well. Remove to cool.
Place the tortilla chips in a food processor or plastic bag and crush/blend into crumbs.
In a large bowl, mix the egg whites, yogurt, salsa, cheddar, and optional jalapeños together. Fold in the cooked beef and tortilla chips.
Spoon the mixture into the muffin mold (about 1/4 cup each).
Bake for 22-24 minutes or until the taco bites are cooked in the center and begin to pull away from the edges of the muffin mold.
Serve with salsa, Greek yogurt or sour cream, or your choice of condiments. Refrigerate leftover taco bites in an airtight container for up to 3-4 days. (You can also freeze them.)