Start by placing your 6 poblano peppers on a foil-lined baking sheet. Roast them under the broiler, flipping once, until the skin is charred on all sides. This should take about 10-15 minutes. Once roasted, seal them in a ziplock bag or wrap them in a damp kitchen towel to steam for 10 minutes. This step makes peeling the skin incredibly easy.
Peel the skin off the cooled peppers, slice them open, and remove the seeds and stems. Dice the peppers into small pieces and toss them with 2 cups of shredded jack cheese for your filling.
Next, blend 3 medium tomatoes, 1/4 large white onion, and 3 garlic cloves in a blender until smooth. Heat 2 tablespoons of vegetable oil in a skillet, pour in the tomato mixture, season with salt, pepper, and 1 bay leaf, and simmer for 10 minutes.
Preheat your oven to 400°F. Heat the 2 tablespoons of vegetable oil in a skillet over medium heat and quickly cook each of the 6 tortillas until soft, about 15-20 seconds per side. Lay the softened tortilla flat, spoon in some of the cheese and poblano mixture, roll it up, and place it seam-side down in an oven-safe dish. Repeat with the remaining tortillas.
Pour the tomato sauce over the enchiladas, making sure to cover them well. Sprinkle the reserved cheese down the middle of the enchiladas. Place the dish in the oven and bake uncovered for 15 minutes, or until the cheese is bubbly and golden.
Remove the enchiladas from the oven and garnish them with fresh cilantro, sour cream, or queso fresco. Serve immediately while they’re hot and gooey, with your favorite side dishes like Mexican rice or refried beans.