Preheat the oven to 450°F (230°C). Line a baking sheet with baking paper.

Place the sun dried tomatoes and kale into a food processor or high-speed blender and blitz until minced.

In a large bowl, combine the ground turkey, minced sun dried tomatoes, kale and crumbled feta cheese. Form the mixture into four burgers and lay them on the baking sheet. Place the sheet into the hot oven and bake for 7 minutes, then flip the burgers over and cook for an additional 5-7 minutes or until cooked through. Remove the burgers from the oven and assemble the buns.

Toast the buns and spread each bun with 1 tablespoon of mayonnaise. Place ¼ of avocado on the bottom of each bun and add the burger. Next top the burgers with tomato and lettuce leaves, before covering with the top bun. Serve immediately.