Slice the pork loin into ¼ inch rounds. Then slice each round into slivers. Sprinkle cornstarch and white pepper over the pork loin and toss to coat the strips in the cornstarch.
Slice the onion into ¼ slivers and grate fresh ginger.
In a small measuring pitcher, combine the soy sauce, mirin, granulated sugar, ginger, and garlic paste. Mix well.
Set a large skillet (or wok) over medium-high to high heat. Pour the oil into the skillet and swirl around the pan. Once hot, place the pork strips into the skillet and stir fry for 2-3 minutes, until the edges are brown.
Add the onions and continue to stir fry for 1-2 minutes until the onions are seared around the edges.
Then pour the ginger sauce into the pan. Toss and simmer the pork and onions in the ginger sauce for 2-3 minutes until the sauce thickens around the pork.
Serve warm with rice and sautéed vegetables on the side.
