Easy side: Prepare 2 (8.5-oz.) packages ready-to-serve roasted garlic whole grain rice according to package directions. Stir in 1 (8-oz.) can sweet whole kernel corn, drained, and 1/4 cup chopped fresh cilantro.
Brush steak with 1 Tbsp. oil; sprinkle with seasoning.
Heat a cast-iron grill pan over medium-high heat; cook steak in pan 7 to 9 minutes on each side or to desired degree of doneness.
Process cilantro, next 3 ingredients, and remaining 4 Tbsp. oil in a food processor until smooth. Cut steak diagonally across the grain into thin slices. Serve sauce with steak.