Adjust rack to top position (top and middle positions for 4 servings) and preheat oven to 425 degrees. Wash and dry produce. Trim, peel, and cut carrots into ½-inch-thick rounds. Zest and quarter lemon. Trim and thinly slice scallions, separating whites from greens.

In a small pot, combine jasmine rice, ¾ cup water (1½ cups for 4 servings), and a big 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, toss carrots on one side of a baking sheet with a drizzle of olive oil, salt, and pepper. (For 4 servings, spread out across entire sheet.) Roast carrots on top rack for 10 minutes (you'll add the pork then).

Meanwhile, pat 10 oz pork filet (20 oz for 4 servings) dry with paper towels; season all over with 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. Once carrots have roasted 10 minutes, stir carrots and carefully place seared pork on opposite side. (For 4 servings, place pork on a second sheet; roast on middle rack.) Return to top rack and roast until pork is cooked through and carrots are tender, 10-12 minutes more.

When pork and carrots have 5 minutes left, melt 1 TBSP butter in pan used for pork over medium-high heat. Add scallion whites and cook until fragrant, 1-2 minutes. Stir in bulgogi sauce and 1 TBSP water. Bring to a simmer, stirring, until warmed through, 2-3 minutes. Turn off heat. (TIP: If sauce is too thick, stir in a splash more water.)

Fluff rice with a fork. Stir in half the lemon zest (add more if you like), 1 TBSP butter, and a squeeze of lemon juice; season with salt and pepper. Thinly slice pork crosswise. Divide rice, pork, and carrots between plates. Drizzle pork with sauce. Sprinkle with scallion greens and sesame seeds. Serve with remaining lemon wedges on the side.