I cup bread crumbs • unsalted butter • ⁄3 white onion, minced • garlic, minced • ⁄4 tsp ground allspice • kosher salt, or to taste • ⁄4 tsp white pepper, freshly ground, or to taste • ⁄2 cup milk • Worcestershire sauce • ⁄4 lb lean ground beef • ⁄2 lb lean ground pork • large egg, plus 1 egg white, beaten •
