Sometimes, you just can't beat a good quesadilla at the end of a long day. These cheesy, flat delights are great whatever the filling, but caramelized onions and browned mushrooms make for a sweet, umami-bursting package. You'll top them with a spicy punch of jalapeño-cilantro relish, cooling avocado, and sour cream. Long day made short with these bad boys in your hands.
Mince cilantro, stems and leaves.
Stem jalapeño, halve, seed, remove ribs, and mince. Retain seeds for extra spice.Be sure to wash hands, utensils, and cutting board after working with jalapeño.
Halve lime and juice.
Combine cilantro, garlic (to taste), jalapeño (to taste), 1 Tbsp. olive oil, 1 Tbsp. water, 2 tsp. lime juice, and a pinch of salt and pepper in a mixing bowl.
Prepare the Remaining Ingredients
Slice mushrooms into ¼" slices.
Halve and peel onion. Slice halves into thin strips.
Cook the Filling
Place a large non-stick pan over medium heat and add 2 tsp. olive oil.
Place mushrooms and onion in hot pan. Stir occasionally until browned, 10-12 minutes.
Season with ¼ tsp. salt and a pinch of pepper. Remove from burner.
Bake the Quesadillas
Place three tortillas on prepared baking sheet. Divide half the cheese and filling between tortillas. Top with remaining cheese and cover with remaining tortillas.
Lightly coat top tortillas with cooking spray and cover with foil, then stack a second baking sheet on top. Place a casserole dish or heavy oven-safe pan on top of baking sheet to "press” quesadillas as they cook.
Bake until tortillas are golden brown, 18-20 minutes. Transfer to cutting board and let rest 5 minutes.
Mash the Avocados
Halve avocado and remove pit by carefully tapping pit with the blade of your knife so it sticks. Gently twist knife to release pit. Scoop out the flesh with a spoon into another mixing bowl.
Season with a pinch of salt and 1 tsp. lime juice and mash until desired consistency is reached.
Plate dish as pictured on front of card, garnishing with relish and sour cream. Bon appétit!