Recipe by Chef Laura Kenny, Real Food Catering
In a medium bowl, mix spices, herbs and Worcestershire. Add lamb and feta cheese and mix well. Season lightly with salt and pepper. Form into 4 equal patties, cover and refrigerate 30 minutes. Heat grill and brush with oil. Grill patties on both sides until desired doneness (145-150°F).
For arugula pesto, boil 8 cups salted water in a medium pot. Submerge arugula in water 10-15 seconds and transfer to an ice bath (bowl with ice and water) to cool. When cool, ring out excess water and roughly chop. Place arugula in blender with garlic, parmesan, and pine nuts. Blend to combine then, while blender is on, stream in olive oil. Blend until smooth. Season to taste with salt and pepper. Set aside.
To assemble, slice buns in half and place on grill to toast. Layer bottom bun with mayonnaise, tomato and lettuce. Top with lamb burger, arugula pesto and top bun.