In 10-inch skillet over medium-high heat add beef and cook, stirring often, until evenly browned, about 5 minutes. Meanwhile, in a large bowl add beans and mash until paste-like. Once beef is browned, drain and add to bean mixture. Add enchilada sauce, cilantro, and garlic powder to bowl and mix until combined. Season to taste with salt and pepper.
Move oven rack to middle position and preheat to 425 degrees F. Line baking sheet with foil and set a wire rack inside baking sheet. Lightly spray a wire rack with nonstick cooking spray and set aside.
Wrap 6 tortillas in clean, damp paper towel, place them on plate and cover plate tightly with plastic wrap. Microwave tortillas until hot and pliable, about 60-90 seconds. Working with 1 tortilla at a time, place 3 tablespoons of filling evenly on the lower third of the tortilla. Fold bottom of the tortilla over filling, roll back slightly to tighten tortilla around the filling, and then roll forward tightly. Place rolled taquito seam-side down on the prepared baking sheet. Repeat with remaining corn tortillas as filling.
Spray taquitos with nonstick cooking spray, sprinkle lightly with salt and bake for 15-20 minutes or until golden and crisp. Serve taquitos with guacamole, sour cream, queso sauce, salsa, diced tomatoes, sliced green onions, and cilantro as desired.