1 lb (450g) mixed ground beef, pork, and veal
1⁄3 cup (16g) fresh bread crumbs, or 1⁄3 cup (35g) dried bread crumbs and 2 Tbsp milk
1 medium onion, finely chopped, and sautéed in 1⁄2 Tbsp oil until translucent
1 egg 1 tsp salt black pepper to taste
1⁄2 tsp ground nutmeg
1 Tbsp vegetable oil ketchup, steak sauce, tonkatsu sauce, or a mix, for coating
Put all the ingredients, except the oil and the ketchup, into a bowl and mix well with your hand until the meat is slightly sticky. Divide the mixture into 24 small, flattened balls.
Heat the oil in a large nonstick frying pan over medium-high heat. Put the mini-hamburgers in the pan in batches, with plenty of space around each one. Cook until browned on one side, then flip over, lower the heat and put the lid on the pan. Steam for 5-6 minutes until the hamburgers are cooked through: they will feel firm to the touch when done. Coat the hamburgers with a little ketchup or tonkatsu sauce, or a mix of both, before removing from the pan, and allow to cool completely before packing into a bento box or freezing.
To freeze the hamburgers, arrange in a single layer, ideally on a metal baking sheet. When frozen, pack into a freezer bag or box. Use within a month for optimum quality.
To use frozen precooked hamburgers, gently heat in a dry nonstick frying pan, covered, over medium-low heat for 8-10 minutes until warmed through. Alternatively, place on a microwave-safe plate and loosely cover with plastic wrap. Microwave on high for 4-5 minutes. Cool to room temperature before packing into a bento box.
I have used a typical meatloaf mix of ground beef, pork, and veal, but you could use all beef instead. If using beef, choose one that is at least 10% fat (labeled “90% fat free”) or your burgers may be rather dry. The amounts given here make enough to stock extra mini-hamburgers in your freezer. I usually make these in advance, since dealing with raw ground meat first thing in the morning isn’t something I like to do!
Recipes and photos from The Just Bento Cookbook © 2010, 2011 by Makiko Itoh. Photography © 2010, 2011 by Makiko Doi