Add the corn kernels and corn “milk,” bell pepper and garlic to the pan and cook, stirring, until the garlic is fragrant, about 2 minutes. Add the reserved cooking liquid and wine and continue cooking, stirring occasionally, until the corn is tender, about 3 minutes more. Stir in sour cream and the remaining ¼ teaspoon each salt and pepper. Sprinkle flour over the mixture. Cook, stirring, until the sauce is bubbling and thickened, about 1 minute.