Heat oil in a skillet over medium heat. Add jalapeno and bell pepper. Cook for 5 minutes. Add all other other tofu ingredients, stir to combine and cook for 8-10 minutes until the tofu is browned.
If you need to make tostada shells from taco shells, preheat oven to 425 degrees and add taco shells to a sheet pan lined with parchment paper. Brush each side with oil. Top with an oven safe cooling rack and bake for 8-10 minutes until crisp.
While the tofu is cooking make your sauce by adding all sauce ingredients to a blender or food processor and blend until smooth.
Assemble tostadas by topping shells with tofu and then drizzling over sauce. Top with red onion if using. Enjoy!
Notes
This recipe makes 2-3 servings depending on how hungry you are.*Some stores sell tostada shells but I made mine from taco shells.** I used a cheese grater to shred mine.