Churrasco means different things in different parts of Latin America: a particular cut of beef in Argentina, a general term for barbecue in Brazil, and a flat tenderloin in Nicaragua. For this dish, the steak is cut in the Nicaraguan style, seasoned with Salvadoran spices, and accented with a Chilean sauce called pebre. (Recipes by Steven Raichlen, award-winning author of Healthy Latin Cooking.)
Place a large skillet coated with cooking spray over medium heat until hot. Add sliced onion and sugar; cover and cook 10 minutes or until golden brown, stirring frequently. Keep warm.
Cut tenderloin lengthwise with the grain into 6 even steaks. Place 1 steak between 2 sheets of heavy-duty plastic wrap; flatten to an even thickness using a meat mallet or rolling pin. Repeat procedure with remaining steaks. Combine salt and next 4 ingredients (salt through cumin). Rub salt mixture over both sides of steaks. Place steaks on a broiler pan coated with cooking spray. Broil 2 minutes on each side or until desired degree of doneness. Top each steak with onion mixture; drizzle each with 1 tablespoon Pebre.