Wash and dry all produce. Trim, then thinly slice scallions. Drain and rinse beans.

Melt 2 TBSP butter in a medium pot over medium-high heat. Add half the scallions. Cook until softened, 1-2 minutes. Stir in rice, beans, and half the spice blend (1 packet). Season with plenty of salt and pepper. Add 3/4 cup water and 1 tsp salt; bring to a boil. Cover and reduce to a gentle simmer. Cook until tender, about 15 minutes.

Quarter tomatoes. Zest 1 tsp zest from lime, then cut into quarters. In a small bowl, toss tomatoes, remaining scallions, half the lime zest, juice from two lime quarters, and a large drizzle of olive oil. Season with plenty of salt and pepper.

Heat a drizzle of olive oil in a medium pan over medium-high heat. Add pork and remaining spice blend, breaking up meat with a spatula or wooden spoon. Season with salt and pepper. Cook, tossing occasionally, until browned, 4-5 minutes. Meanwhile, stir together sour cream, remaining lime zest, and a squeeze of lime juice in another small bowl. Season with salt and pepper.

Fluff rice and beans with a fork once done, then stir in a big squeeze of lime juice. Reduce heat under pan with pork to medium, then toss in rice and beans as well as half the cheese. Allow mixture to warm through, 1-2 minutes. Season with plenty of salt and pepper.

Divide rice mixture between bowls and top with salsa. Garnish with remaining cheese and dollop with crema. Serve with any remaining lime quarters for squeezing over.