1. Prepare the peppers. Line a large baking sheet with aluminum foil and place poblano peppers on top. Set your oven rack directly underneath the broiler and turn the broiler on. Broil poblanos for 5 minutes, or until the skin is blackened and blistered. Carefully flip them over and broil for another 5 minutes. Remove the peppers from the oven and cover tightly with aluminum foil or plastic wrap to keep in the heat and steam. Let the peppers sit for 10 minutes.
2. Peel and rub off as much of the loose blackened skin on the peppers as possible. Don’t worry if you can’t get it all off.
3. Cut a small slit down the middle of the peppers. Remove seeds and stuff the peppers with the cheese. Close the opening of the peppers and secure with toothpicks. Set aside.
4. Heat the oil in a deep skillet over medium-high heat. Line a plate with paper towels and set to the side. While oil is heating up, prepare the batter.
5. Separate the egg whites from the yolks into two separate bowls. Place the whites into a large mixing bowl and the yolks into a small bowl. Using an electric hand mixer, beat the egg whites until stiff peaks form. While continuing to beat the egg whites on low, add in the egg yolks one at a time until they are all fully mixed in. The batter should be light, fluffy and smooth.
6. Place the flour and salt onto a plate and stir to combine. Use a spoon and sprinkle the flour mixture over stuffed peppers, tap to remove any excess. Then dip the peppers in the egg batter. I use a spoon to cover the pepper to avoid flipping the pepper too much. Remove excess batter and gently place them in the hot frying oil.
7. Fry the peppers 3-5 minutes per side, until the batter is golden brown and crispy. Try not to overcrowd the peppers in the pan. I usually fry no more than 2 at a time. Transfer the peppers to the paper towel-lined plate to drain off any excess oil. Remove the toothpicks.
8. Immediately serve chile Rellenos on a plate with the salsa Roja, freshly chopped cilantro, and topped with cotija cheese.

Salsa Roja

1. Add tomatoes, onion, garlic, jalapeno, cilantro and salt to a blender. Puree until smooth.
2. Heat olive oil in a small saucepan over medium-high heat. Add blended salsa and bring to a boil.
3. Reduce heat to low and simmer, stirring occasionally for 8 minutes. Remove from heat, taste and season with more salt if desired.