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

Peel sweet potatoes; dice into ½-inch pieces.

Place sweet potatoes in a medium pot with enough salted water to cover by 2 inches. Bring to a boil and cook until tender when pierced with a fork, 15-20 minutes. TIP: Cover pot with a lid to bring to a boil more quickly.

Drain sweet potatoes and return to pot. Cover to keep warm.

While sweet potatoes cook, place 2 TBSP butter (4 TBSP for 4 servings) in a small bowl; bring to room temperature.

Place peppercorns in a zip-close bag and crush with a rolling pin or heavy-bottomed pan.

Trim and discard bottom 1 inch from asparagus. Pick sage leaves from stems; finely chop leaves until you have 1 TBSP (2 TBSP for 4). Quarter lemon.

Toss asparagus on a baking sheet with a drizzle of oil, salt, and pepper. Roast on top rack until browned and tender, 10-12 minutes.

Meanwhile, pat steak* dry with paper towels; season all over with salt and pepper.

Heat a drizzle of oil in a large pan over medium-high heat. Add steak and cook to desired doneness, 3-6 minutes per side.

Turn off heat; transfer steak to a cutting board to rest for at least 5 minutes. Wipe out any burned bits from pan.

While steak rests, heat a drizzle of oil in same pan over medium-low heat. Add ½ tsp crushed peppercorns (1 tsp for 4 servings). (Be sure to measure peppercorns—we sent more.) Cook, stirring, until fragrant, 30 seconds.

Stir in ¼ cup water (⅓ cup for 4) and stock concentrate. Simmer until thick enough to coat the back of a spoon, 1-3 minutes.

Remove pan from heat; stir in half the crème fraîche and 1 TBSP butter (2 TBSP for 4) until melted and combined. Cover to keep warm. TIP: If sauce seems too thick, add a small splash of water.

To bowl with softened butter, add half the maple syrup (all for 4 servings), half the garlic powder, 1 tsp chopped sage (2 tsp for 4), salt, and pepper. Using a fork, stir to combine. TIP: If needed, microwave butter for 10-15 seconds to soften.

To pot with sweet potatoes, add half the maple sage butter (save the rest for serving), remaining crème fraîche, remaining chopped sage, and remaining garlic powder. Mash with a potato masher or fork until smooth and creamy. Season with salt and pepper.

If asparagus has cooled, reheat in oven for 2-3 minutes.

Slice steak against the grain.

Divide steak, sweet potatoes, and asparagus between plates. Spoon sauce over steak. Top sweet potatoes with remaining maple sage butter. Top asparagus with a squeeze of lemon juice; serve with any remaining lemon wedges on the side.