5 Cook for 4-5 minutes, or until the pieces float to the surface. Drain, reserving some of the cooking water. 6 Spinach pesto Add all the ingredients to a blender and season with salt to taste. Blitz ...
Top with the cheese and grill until the burgers are cooked through and the cheese is melted, about 5 minutes longer. Spread the pesto on the rolls. Top with the burgers and spinach and serve.