Preheat oven to 200 degrees. Halve, peel, and slice the onion. Halve the zucchini lengthwise, then slice into 1/4-inch half moons. Thinly slice the romaine lettuce. Drain and rinse the kidney beans. Halve, core, seed, and chop the tomatoes. Zest and juice the lime. Finely chop the jalapeño, removing the seeds if you prefer less heat.

Heat 1 tablespoon olive oil in a large pan over medium heat. Add the onion and season with salt and pepper. Cook for about 5 minutes, until softened, and set aside. Add the zucchini and cook, tossing, for 2-3 minutes, until softened and lightly charred.

Return the onion to the pan, then add the kidney beans, cumin, chipotle powder, tomatoes, and as much jalapeño as you dare. Cook for about 5 minutes, until tomatoes have softened. Taste and season with salt and pepper. Set aside.

Make the lime crema: in a small bowl, thoroughly combine the sour cream with the lime zest. Set aside.

Wipe the pan clean with paper towel. Heat one tortilla over medium heat. Sprinkle one half of the tortilla with mozzarella cheese, top with some zucchini and kidney beans, and top with more cheese. Fold over the tortilla and turn. Cook until cheese has melted, and tortilla is crispy, about 3 minutes. Transfer the quesadilla to a baking sheet and place in the oven to keep warm. Repeat to make the other quesadilla.

Make the romaine salad: toss the romaine lettuce with lime juice, 1/2 tablespoon olive oil, salt and pepper.

Cut the quesadillas into wedges. Serve with the lime crema and the romaine salad to the side.