Adjust rack to middle position and preheat oven to 425 degrees. Bring a large pot of salted water to a boil. Wash and dry produce.

Halve, peel, and dice onion into ½-inch pieces. Dice tomatoes into ½-inch pieces.

Place 1 TBSP butter (2 TBSP for 4 servings) in a small microwave-safe bowl. Cover with plastic wrap and microwave until melted, about 30 seconds. Stir in panko, salt, and pepper.

Once water is boiling, add cavatappi to pot. Cook, stirring occasionally, until al dente, 9-11 minutes.

Reserve ¼ cup pasta cooking water, then drain. (Reserve pot for Step 4.)

While pasta cooks, heat a drizzle of oil in a large pan over medium-high heat. Add onion and a pinch of salt; cook, stirring occasionally, until beginning to soften, 2-3 minutes.

Add beef* and tomatoes; season with salt and pepper. Cook, breaking up meat into pieces, until browned and cooked through, 4-5 minutes.

Turn off heat and stir in garlic powder and stock concentrate; taste and season with more salt and pepper if desired. Transfer mixture to an 8-by-8-inch baking dish (9-by-13-inch baking dish for 4 servings).

In pot used for pasta over medium heat, combine cream sauce base, cream cheese, and 2 TBSP reserved pasta cooking water (4 TBSP for 4 servings). Cook, stirring constantly, until cream cheese melts, 1-2 minutes.

Turn off heat; stir in Monterey Jack until melted and combined.

Top beef mixture with drained cavatappi, then drizzle with sauce (cover as much surface as you can—it doesn’t have to be perfect!). Top evenly with mozzarella and panko mixture.

Bake on middle rack until top is browned and bubbly, 10-15 minutes.

Let pasta bake rest for at least 3 minutes before serving.

Divide pasta bake between plates and serve.