Slice chicken breasts into thin strips or bite-sized pieces. In a bowl combine olive oil, cumin, chili powder, garlic powder, salt, pepper and lime juice. Toss chicken in the marinade to coat and let rest 10 minutes. Heat a medium skillet over medium-high heat. Add a drizzle of oil if needed and cook chicken 4–6 minutes, stirring occasionally, until cooked through and lightly browned. Remove from heat and set aside.

Keep warm while assembling quesadillas.

Filling — Skirt steak

Season and cook steak

Trim excess fat and slice steak across the grain into thin strips. Toss steak with olive oil, cumin, smoked paprika, minced garlic, salt, pepper and lime juice. Heat a heavy skillet or grill pan over high heat until very hot. Sear steak strips 1–2 minutes per side for medium-rare (longer if desired). Remove and let rest 5 minutes, then slice thinner if needed.

Keep warm while assembling quesadillas.

Filling — Mariscos (mixed seafood)

Cook seafood

Pat seafood dry. In a bowl toss shrimp and chopped scallops/fish with olive oil, minced garlic, smoked paprika, salt and lime juice. Heat a skillet over medium-high heat. Add the seafood and cook quickly: shrimp 1–2 minutes per side and scallops/fish until opaque and just cooked through (total 3–4 minutes). Remove immediately to avoid overcooking.

Keep warm while assembling quesadillas.

Assemble & Cook Quesadillas

Assemble

Lay one flour tortilla on a flat surface. Sprinkle a thin, even layer (about 1/2 cup) of the cheese blend over half of the tortilla, add a portion of your chosen cooked filling (about 3–4 oz per quesadilla), scatter a few slices of white onion and a teaspoon of chopped cilantro, then top with another 1/4 cup of cheese (this helps the top tortilla stick). Fold the empty half of the tortilla over to create a half-moon.

Cook

Heat a large nonstick or cast-iron skillet over medium heat and add 1/2 tsp butter or oil. Place the folded quesadilla seam-side down and cook 2–3 minutes until golden and the cheese begins to melt. Flip carefully and cook another 1–2 minutes until both sides are golden brown and cheese is fully melted. Repeat with remaining tortillas, adding more oil/butter as needed. Press lightly with a spatula for even contact.

Finish

Transfer cooked quesadillas to a cutting board and let rest 1 minute, then cut into 2 or 3 wedges. Keep warm in a low oven (200°F / 95°C) if making several.

Serve

Arrange quesadilla wedges on a platter with lime wedges, sour cream and pico de gallo or salsa on the side. Garnish with remaining chopped cilantro.

Serve immediately while hot and cheesy.