In a large bowl, combine the flour and baking powder; add the milk and form a soft dough. Knead until mixed thoroughly. Cover and let rest 30 minutes.

Meanwhile, brown the beef and garlic in large skillet until meat is no longer pink; drain well. Add the chilies, taco seasoning, salt and pepper if desired, and water. Simmer uncovered for 10 minutes.

Stir in the beans and heat through; keep warm.

In a deep fat fryer or skillet, preheat oil to 375.

Separate the dough into 6 equal portions. Roll over lightly floured surface into a 7 inch circle.

Fry the tostadas in hot oil until golden, turning once; drain on paper towels.

Immediately top each tostada with meat mixture and desired toppings.