Mix mashed potatoes, egg, salt, pepper, chicken and cheese in a bowl. Form small amounts into croquettes.
Sprinkle flour over the croquettes. Place beaten eggs in a shallow bowl; place breadcrumbs in a separate shallow bowl. Dip croquettes into the egg and then into the breadcrumbs, making sure they are coated completely. Heat oil in a large skillet and fry the croquettes until lightly browned. Drain on paper towels.
Place tomatoes, onion, garlic and CONSOMATE® Concentrate in a blender; cover. Blend until smooth. Serve with croquettes.