How to Make It
In a small bowl, combine the ground ginger with the chile powder, pimentón, garlic, 1 tablespoon each of kosher salt and pepper and the vegetable oil. Rub the mixture all over the short ribs. Transfer the short ribs to 2 resealable plastic bags and refrigerate overnight.
Preheat the oven to 325°. Arrange the ribs on a large rack set over a large rimmed baking sheet. Bake for about 1 hour and 30 minutes, or until most of the fat has been rendered. Remove the ribs from the rack and set them directly on the baking sheet. Cover with foil and bake for about 2 hours longer, or until tender. Let cool slightly, then discard the bones and trim any gristle, keeping each piece of meat intact.
Increase the oven temperature to 425°. On another large rimmed baking sheet, toss the cipollini onions with the 2 tablespoons of olive oil. Season the onions with salt and pepper and roast for about 15 minutes, or until golden brown and tender.
Light a grill or preheat the broiler. Drizzle the ribs with olive oil and grill over high heat for about 2 minutes per side, or until nicely charred. Transfer to plates and serve with the roasted onions, Hazelnut Romesco Sauce and lemon wedges.
Flanken-style short ribs are sliced 1/2 inch thick across the third or fourth ribs.