In a large nonstick skillet, heat oil over medium-high heat; saute onion 2 minutes. Add garlic; cook and stir 1 minute. Stir in carrot and spices; cook and stir until carrot is tender, 2-3 minutes. Remove from heat., In a large bowl, mash pinto and black beans using a potato masher. Stir in mustard, soy sauce, ketchup and carrot mixture. Add oats, mixing well. Shape into eight 3-1/2-in. patties. , Place burgers on an oiled grill rack over medium heat or on a greased rack of a broiler pan. Grill, covered, or broil 4 in. from heat until lightly browned and heated through, 4-5 minutes per side. Serve on buns with lettuce and salsa.