4 portobello mushroom caps, cut into strips
2 green bell peppers, cut into strips
2 small yellow squash, cut into strips
1 medium onion, chopped
1/2 Serrano chili, seeded, minced
1 garlic clove, chopped
1 tablespoon chili powder, or to taste
1 teaspoon cumin
1 cup cooked beans, any type or canned low-sodium or no-salt-added beans, drained
3 tablespoons chopped fresh cilantro
2 tablespoons raw pumpkin seeds, lightly toasted
4 large (100% whole grain) flour tortillas
1 ripe avocado, peeled and sliced