This was inspired by the grilled ham and cheddar cheese sandwiches we served at lunch at one of my first cooking jobs in Weston, Vermont. Of course, there is no bread here, but freshly toasted corn tortillas instead.
In a small bowl, whisk together the lime juice, paprika, and 3 tablespoons oil. Mix in the onion, cilantro, and sugar to make a dressing, then season to taste with salt and pepper. In a salad bowl, combine the spinach and apple.
Brush a large nonstick frying pan with olive oil and warm over medium-high heat. Add the sausage and sauté until beginning to brown, about 2 minutes. Transfer to a small bowl. Add the red pepper and sauté until tender and starting to brown, about 5 minutes. Transfer to another small bowl.
Heat a griddle or large frying pan over medium-low heat. Brush with olive oil. Add 2 tortillas and cook until softened slightly, about 30 seconds. Turn over and sprinkle 2 tablespoons of the cheese over half of each tortilla, leaving a border. Top with 1 tablespoon of the sausage and 1 tablespoon of the bell pepper. Sprinkle with 2 tablespoons of the cheese. Fold the empty side of the tortillas over the filling and press slightly. Cook until light golden and crisp, 2–3 minutes on each side. Transfer to warmed plates. Repeat with the remaining tortillas, cheese, sausage, and bell pepper, adding oil as needed.
Dress the salad to your liking and toss to coat the leaves. Serve right away with the quesadillas.