Cook pancetta in a pan, saving rendered fat. After it's cooled, chop pancetta and mix with reserved fat and butter in a bowl. Add shallot, garlic, parsley, lemon juice and zest. Mix and season with salt and pepper to taste. Place on parchment paper or plastic wrap, rolling to create a tube. Put in refrigerator until ready to use. Grill steaks to desired doneness, see chart on pages 4-5. Let steaks rest for 5 minutes. Remove butter tube from refrigerator and slice, placing a palette of butter on each steak.