Preheat the oven to 400°F.
Brush both sides of the tortillas with vegetable oil.
Bake the tortillas for 5 to 7 minutes per side until golden and crispy.
Brown the ground beef in a skillet over medium heat and drain excess grease.
Stir in the taco seasoning and water and simmer for 5 minutes.
Warm the refried beans until spreadable.
Spread refried beans evenly over 6 crispy tortillas.
Top with seasoned beef and a drizzle of nacho cheese sauce.
Place the remaining tortillas on top to create the second layer.
Spoon enchilada sauce generously over each pizza.
Cover with cheddar and Monterey Jack cheese.
Bake for 8 to 10 minutes until the cheese is melted and bubbly.
Top with diced tomatoes, green onions, and black olives.
Add generous dollops of sour cream.
Garnish with cilantro if desired and serve immediately.