Preheat the oven to 220°C/200°C fan/Gas 7 and line two large baking trays with baking paper.
Place a large, non-stick frying pan over a high heat, add the oil and onion and cook for 2–3 minutes, or until the onion has softened. Add the garlic and cook for 2 minutes, then crumble in the minced beef. Cook over a high heat for 4–5 minutes, or until the mince is lightly browned.
Stir in the spices and cook for 1–2 minutes. Add the tinned tomatoes, cook for 2 minutes, then remove from the heat. Stir in the kidney beans and season to taste.
Lightly brush one side of a tortilla with extra oil and place on a prepared tray, oiled side down. Sprinkle a little cheese over one half and spread a quarter of the beef mixture on top. Scatter some spring onions, jalapeňos and cheese on top before folding over the tortilla. Repeat for the remaining tortillas.
Brush one side of the 2 remaining tortillas with oil and place on top of the beef filling, oiled side up. Press them down firmly and place on the two highest shelves of the oven for 10–15 minutes, or until golden brown.
While the quesadillas are cooking, mix all the salsa ingredients in a bowl and season to taste.
Remove the quesadillas from the oven and cut into wedges before serving with a dollop of sour cream and some salsa on the side.

Mexican Beef and Jalapeño Quesadillas