Place beef and seasoning in a Multipurpose Steamer. Cover; microwave for 2 minutes on high. Using a fork, break up meat. Cover and microwave until cooked through, 2–3 more minutes. Drain and discard liquid.
Preheat oven to 425° F (220° C).
Arrange naan on 2 Sheet Pans. Spread yogurt overtop; drizzle with Chimichurri sauce.
Sprinkle beef, tomatoes, and cheese on top. Bake until edge is crisp and cheese melts, about 10 minutes.
Top with arugula.
Preheat grill to medium.
Place naan on grill for 1 minute.
Remove; spread grilled sides with yogurt, Chimichurri, beef, tomatoes, and cheese. Grill until edges are crisp and cheese melts, 2–3 minutes.