Quesadillas with leftover steak

1 small spring onion, finely chopped 1 tbsp olive oil 1/2 red bell pepper, finely chopped 1 tomato, diced ½ clove garlic, minced ½ tsp smoked paprika 1 cooked steak, sliced thin 2 medium tortillas 100 g shredded cheddar 1 chopped fresh coriander

For serving

2 tbsp strained yogurt ½ tsp smoked paprika