Adjust rack to top position and preheat oven to 425 degrees. Wash and dry produce.

Cut potatoes into ½-inch-thick wedges. Trim and thinly slice scallions, separating whites from greens; finely chop whites until you have 1 TBSP (2 TBSP for 4 servings). Finely chop chili. Trim, peel, and grate carrot on the largest holes of a box grater; place in a medium bowl.

Cut broccoli into bite-size pieces if necessary. (Save potatoes for another use.)

Toss potatoes on a baking sheet with a drizzle of oil, salt, and pepper.

Roast on top rack until golden brown and crispy, 20-25 minutes.

Meanwhile, in a small bowl, combine mayonnaise, mustard, chopped scallion whites, one packet sour cream (two packets for 4 servings), 1 tsp vinegar (2 tsp for 4), and a pinch of chili to taste. (You’ll use the rest of the sour cream and vinegar later.) Season with salt and pepper. Set aside.

Swap in broccoli for potatoes; roast until browned and tender, 15-20 minutes. 

To bowl with carrot, add cabbage, two packets sour cream (four packets for 4 servings), remaining vinegar, 2 TBSP scallion greens (4 TBSP for 4), and 1½ tsp sugar (3 tsp for 4). (You’ll use the rest of the sour cream in the next step.)

Season with a big pinch of salt and pepper; toss to combine.

Halve tilapia fillets* lengthwise. (You’ll have a larger piece and a smaller piece.) Pat dry with paper towels.

In a shallow dish, combine Old Bay Seasoning, remaining sour cream, and 1 TBSP water (2 TBSP for 4 servings).

On a plate, combine panko and cornstarch.

Dip each fillet into sour cream mixture, then press into panko mixture, coating all over.

Heat a ⅓-inch layer of oil in a large, preferably nonstick, pan over medium-high heat. Once oil is hot enough that a pinch of panko mixture sizzles when added to pan, add tilapia and cook until crust is golden and fish is cooked through, 2-3 minutes per side (the smaller pieces will cook faster). (For 4 servings, fry fish in batches.)

Transfer to a paper-towel-lined plate.

Divide potatoes, slaw, and tilapia between plates. Serve with spicy remoulade. Garnish with any remaining scallion greens.