HEAT OLIVE OIL IN A LARGE STOCKPOT OR DUTCH OVEN OVER MEDIUM HIGH HEAT. ADD GROUND BEEF AND COOK UNTIL BEEF HAS BROWNED, ABOUT 3-5 MINUTES, MAKING SURE TO CRUMBLE THE BEEF AS IT COOKS; STIR IN TACO SEASONING. DRAIN EXCESS FAT.
STIR IN RO*TEL®, TOMATO PASTE, SPAGHETTI AND 3 CUPS WATER. BRING TO A BOIL; COVER, REDUCE HEAT AND SIMMER UNTIL PASTA IS COOKED THROUGH, ABOUT 13-16 MINUTES.
REMOVE FROM HEAT AND TOP WITH CHEESES. COVER UNTIL MELTED, ABOUT 2 MINUTES.
SERVE IMMEDIATELY, GARNISHED WITH TOMATO AND CILANTRO, IF DESIRED.