1. Remove strings or sinew from livers. Sprinkle with the salt and pepper. Dredge lightly in flour; shake off excess.

2. Heat olive oil and 2 tablespoons butter in a medium saute pan over medium heat. Saute livers in two batches (using more butter and oil if necessary with the second batch) until nicely browned and still pink in the center, about 2 minutes on each side.

3. Remove livers from saute pan; place on a plate, covered with foil, to keep warm. Drain off all but 1 tablespoon fat; discard. If there is not enough fat in pan, add more olive oil. Add shallots and herbs; saute until shallots are soft and slightly browned, about 2 minutes. Add Marsala; simmer until reduced by half, about 2 minutes. Add stock; simmer until reduced by half, about 3 minutes.

4. Remove pan from heat, and swirl in remaining butter. Season with salt and pepper. Pour sauce over livers before serving.