Sauté the vegetables. Heat the oil in a large frying pan over medium-high heat. Add onion and season with salt and pepper. Cook stirring occasionally until onion just starts to become tender. Add garlic and poblanos and season again with salt and pepper. Cook until peppers are starting to become tender then add zucchini and summer squash, cook a few minutes, then add tomatoes, oregano, and cumin. Continue cooking, stirring occasionally until zucchini is just tender, but still has some bite and tomatoes have broken down a bit. Taste and season with more salt and pepper if needed. 

Melt cheese over the top. Sprinkle cheese all over the top covering evenly. Remove from heat. Cover and let cheese melt, about 2-3 minutes. Garnish with fresh cilantro leaves and serve!