Pour the olive oil into a medium skillet and set it over medium-high heat. Add the onions, stir, season with salt and pepper, and cook, stirring often, until they are golden, about 10 minutes. Add the garlic and continue cooking, stirring constantly, for about 1 minute. Remove them from the pan, return the pan to the heat and add the chicken or turkey. Increase the heat so the meat sizzles merrily and cook, stirring constantly, until the meat is golden on all sides and just about cooked through, about 8 minutes. Remove from the heat.