Melt butter and oil in large skillet. Add shallots and cook over low heat 3 minutes. Raise heat, add veal and season to taste with salt and freshly ground pepper. Cook only 2 minutes per side, then remove from heat and keep warm. Add the wine to the pan. Bring to a boil, while stirring, and cook until reduced to a few tablespoons. Whisk in mustard and cream and cook 2 minutes longer. Arrange veal on a platter, pour sauce over, and sprinkle with chopped tomato.