After transferring steaks to large plate, pour off all but 1 tablespoon fat from now-empty skillet. Return skillet to low heat and add shallot; cook, stirring frequently, until beginning to brown, 2 to 3 minutes. Sprinkle flour over shallot; cook, stirring constantly, until combined, about 1 minute. Add wine and increase heat to medium-high; simmer rapidly, scraping up browned bits on pan bottom, until liquid is reduced to glaze, about 30 seconds; add broth and simmer until reduced to 2/3 cup, about 4 minutes. Reduce heat to medium; add capers, tomatoes, and any meat juices, and cook until flavors are blended, about 1 minute. Stir in parsley and season to taste with salt and pepper; spoon sauce over sliced steak.

Makes 3/4 cup