Prepare the Taco Meat
In a skillet over medium heat, cook the ground beef, breaking it into small pieces. Once browned, drain excess grease. Add taco seasoning and water, stirring to combine. Cook for another 2-3 minutes until the mixture thickens. Set aside.

Fry the Tortillas
Heat oil in a small skillet over medium-high heat. Fry each corn tortilla one at a time until golden and slightly crisp on both sides, flipping halfway through. Place fried tortillas on a paper towel to drain excess oil.

Assemble the Pizzas
Preheat the oven to 400°F (200°C).
On a baking sheet, lay out half of the fried tortillas. Spread a thin layer of enchilada sauce on each tortilla, followed by a layer of refried beans and a spoonful of taco meat. Sprinkle shredded cheddar cheese over the meat.
Top each with another tortilla, spread a thin layer of enchilada sauce on top, and finish with more shredded cheese.

Bake
Bake the assembled pizzas in the preheated oven for about 10 minutes, or until the cheese is melted and bubbly.

Garnish and Serve
Remove from the oven and top each pizza with diced tomatoes, sliced olives, and chopped green onions. Add sour cream if desired. Cut into wedges and serve warm.