Heat oil in a non-stick frying pan over medium heat. Add the onion and garlic and cook for 2-3 minutes or until softened. Increase heat to high. Add the mince and cook, stirring, for 5 minutes or until browned.
Add lemon rind, 1 tbs lemon juice, half the thyme and season with salt & pepper. Cook for 2-3 minutes or until lemon has almost been absorbed.
Cut the tops off the Kumato® tomatoes and carefully scoop out the flesh. Spoon mince mixture into Kumato® tomatoes and place into a lightly greased roasting pan. Combine the feta and remaining thyme and sprinkle over the lamb mixture. Bake for 10-15 minutes or until Kumato® tomatoes are warm and top is lightly golden. Serve with tzatziki & crusty bread.