Whisk together the flour, baking powder, and salt in a large mixing bowl. Add the shortening and rub it into the flour with your fingertips until the mixture resembles coarse crumbs.

Pour in the warm water and stir until a shaggy dough forms. Knead the dough on a lightly floured surface for about 2 minutes until smooth and slightly tacky.

Divide the dough into 8 equal portions and roll each into a smooth ball. Cover with a damp kitchen towel and let rest for 15 minutes.

Heat the oil in a medium saucepan over medium heat and saute the garlic for 30 seconds until fragrant. Add the beans with their liquid and the cumin, then mash to your desired consistency. Cook for 5 to 7 minutes, stirring occasionally, until thickened. Season with salt to taste.

Roll each dough ball into a circle about 8 inches in diameter and 1/8 inch thick. Work from the center outward, rotating the dough quarter turns for even thickness.

Heat a dry cast iron skillet or comal over medium high heat until a drop of water sizzles immediately. Cook each tortilla for 45 to 60 seconds per side until brown spots appear and the surface puffs.

Transfer cooked tortillas immediately to a clean kitchen towel and wrap them snugly to keep them warm and pliable.

Spread 2 to 3 tablespoons of warm refried beans down the center of each tortilla. Top with crumbled queso fresco and a generous drizzle of crema. Fold the tortilla in half and serve immediately.