Heat olive oil in a sauté pan and add onion, zucchini, bell pepper and shredded carrot. Cover pan and sauté vegetables until soft, about 20 minutes.
Add chopped spinach and minced garlic and sauté until spinach is wilted and garlic is fragrant.
Next, add one can of black beans that have been drained along with sugar, vinegar, spices and salt. Sauté mixture for about 10 minutes or until mixture has thickened.
While vegetable mixture is thickening, make corn tortillas.
In a bowl, mix together masa and water and let rest for two minutes.
While the dough rests, heat a cast iron skillet.
Scoop ¼ cup of dough in your hands and roll into a ball.
Place the ball between two pieces of plastic wrap and flatten on a hard surface using a baking sheet.
Remove plastic wrap and set aside. Place flattened tortilla in the hot, dry cast iron skillet and toast for 30 seconds on each side. Wrap cooked tortillas in foil to keep warm.
Repeat until you have cooked all 8 tortillas.
To assemble the tacos, lay two tortillas on a plate and generously top with vegetable mixture. Add the toppings of your choice and enjoy! I recommend cilantro, fresh jalapeños and avocado slices. Yum!