Adjust rack to top position (top and middle positions for 4 servings) and preheat oven to 425 degrees.

In a small pot, combine rice, ¾ cup water (1½ cups for 4), and a pinch of salt. Bring to a boil, then cover and reduce to a low simmer. Cook until rice is tender, 15-18 minutes.

Keep covered off heat until ready to serve.

While rice cooks, wash and dry produce.

Cut broccoli into bite-size pieces if necessary.

Swap in beef for pork. Cook to desired doneness, 4-7 minutes per side. Transfer to a cutting board to rest. (Skip roasting in the next step.)

Pat pork* dry with paper towels; season all over with half the garlic powder (you'll use the rest in the next step), salt, and pepper.

Heat a drizzle of oil in a large pan over medium heat. Add pork and sear, turning occasionally, until browned all over, 4-8 minutes (it'll finish cooking in the next step). Transfer pork to one side of a baking sheet. (For 4 servings, spread pork out across entire sheet.)

Skip roasting beef. Spread broccoli across the sheet. Once beef has rested, slice against the grain. 

On opposite side of sheet from pork, toss broccoli with a drizzle of oil, remaining garlic powder, salt, and pepper. (For 4 servings, toss broccoli on a second baking sheet.) 

Roast on top rack until pork is cooked through and broccoli is browned and tender, 12-15 minutes. (For 4, roast broccoli on top rack and pork on middle rack, swapping rack positions halfway through.)

Transfer pork to a cutting board to rest for at least 5 minutes.

While pork and broccoli roast, in a small bowl, combine chimichurri and sour cream.

Thinly slice pork crosswise.

Fluff rice with a fork; stir in 1 TBSP butter (2 TBSP for 4 servings) until melted.

Divide rice and broccoli between plates in separate sections. Top rice with pork; spoon creamy chimichurri over pork. Serve.