Espresso and Lime

0 Place the very thin slices of flank steak between two sheets of plastic wrap or parchment paper and pound each one into uniform thinness
1 Trim the root off of the green onions and lay two over each portion of pounded beef
2 Roll the beef up tightly like a cigar and secure with several toothpicks (optional)
3 Lightly dust each roll with rice flour and shake off the excess (optional)
4 Place a large skillet over medium heat and add a tablespoon of a neutral oil
5 Brown the rolls starting with the seam side for about 3 minutes per side or until the outside is crisp and the inside is about medium rare (about 9 minutes total)
6 Transfer the beef rolls onto a plate, remove the toothpicks, if used, and set aside
7 Add 2 cloves of finely minced garlic, 1 teaspoon of grated ginger, 1/2 cup soy sauce, 1/4 cup of mirin, 2 tablespoons of granulated sugar and 1 tablespoon of toasted sesame oil into the skillet and bring to a simmer
8 Once the sauce thickens, add the beef rolls into the skillet and spoon the sauce over the rolls
9 To serve, slice the rolls into bite sized pieces and garnish with white sesame seeds and thinly sliced green onions
10 Serve over rice or noodles (optional)