Keto Lemon-Dill Butter Salmon Sheet Pan with Asparagus

Why You’ll Love This Recipe

• One pan, minimal cleanup, and dinner on the table in under 30 minutes.
• Bright lemon and fresh dill cut through rich, buttery salmon for balanced flavor.
• Keto-friendly with naturally low carbs and satisfying healthy fats.
• Restaurant-quality results with simple, accessible ingredients.

Grocery List

• Produce: 1 lemon, 1 lb asparagus, fresh dill, garlic (optional), extra lemon for serving
• Dairy: Unsalted butter
• Pantry: Salmon fillets, extra-virgin olive oil, capers, kosher salt, black pepper, red pepper flakes (optional)

Full Ingredients

Salmon & Asparagus

• 4 salmon fillets, skin-on, 6 oz each (about 1.5 lb total)
• 1 lb asparagus, woody ends snapped off
• 1 tbsp extra-virgin olive oil (for asparagus)
• 1 tsp kosher salt, divided
• 1/2 tsp freshly ground black pepper, divided
• Pinch red pepper flakes (optional)

Lemon-Dill Butter

• 4 tbsp unsalted butter, softened
• 1 tsp finely grated lemon zest (from 1 lemon)
• 2 tbsp fresh dill, finely chopped
• 1 small garlic clove, minced (about 1/2 tsp; optional)

To Finish

• 2 tbsp capers, drained (rinse if sensitive to salt)
• 1 tbsp extra-virgin olive oil
• 1 tbsp fresh lemon juice
• Extra dill fronds and lemon wedges, for serving

Step-by-Step Instructions

Step 1: Preheat and prep the pan

Preheat the oven to 425°F with a rack in the center. Line a large rimmed sheet pan with parchment paper for easy cleanup (foil works too). Pat the salmon fillets dry with paper towels and set aside.

Step 2: Make the lemon-dill butter

In a small bowl, mash together the softened butter, lemon zest, dill, and garlic (if using) until evenly combined. This compound butter should be soft and spreadable. Set aside at room temperature so it stays easy to dollop.

Step 3: Season the asparagus

Place the trimmed asparagus on the prepared sheet pan. Drizzle with 1 tablespoon olive oil, sprinkle with 1/4 teaspoon kosher salt, a few grinds of black pepper, and a pinch of red pepper flakes if you like gentle heat. Toss to coat and spread the spears out in a single layer, leaving space for the salmon.

Step 4: Season and butter the salmon

Set the salmon fillets skin-side down on the sheet pan beside the asparagus, leaving a bit of space between fillets. Season the tops with the remaining 3/4 teaspoon kosher salt and the rest of the black pepper. Dot each fillet with about 1 tablespoon of the lemon-dill butter, spreading it lightly over the top.

Step 5: Roast to juicy perfection

Roast at 425°F for 12–14 minutes, depending on fillet thickness, until the salmon is just opaque and flakes easily with a fork. An instant-read thermometer inserted into the thickest part should read 120–125°F for medium. The asparagus should be crisp-tender with lightly browned tips. If you’d like extra browning, broil for 1 minute, watching closely.

Step 6: Finish and serve

Remove the pan from the oven. Sprinkle capers over the hot salmon and asparagus, then drizzle with the remaining 1 tablespoon olive oil and 1 tablespoon lemon juice. Let the salmon rest for 3 minutes so the juices settle. Garnish with dill fronds and serve with lemon wedges. Spoon any buttery pan juices over the salmon at the table.

Pro Tips

• Pat the salmon very dry so the butter clings and the tops brown nicely.
• Choose evenly sized fillets (about 1 inch thick) for consistent cooking.
• Trim asparagus where the stalk naturally snaps; this removes the woody end.
• Pull salmon at 120–125°F for moist, tender results; it will rise a couple of degrees as it rests.
• Rinse capers if you prefer a lower-sodium finish without losing briny brightness.

Variations

• Swap the veg: Broccolini or thin green beans roast beautifully at 425°F for 12–15 minutes.
• Herb twist: Try tarragon or parsley in place of dill, or add 1 teaspoon Dijon mustard to the butter for a tangy kick.
• Dairy-free: Use ghee or a high-quality dairy-free butter substitute to keep it keto and lactose-free.

Storage & Make-Ahead

Make the lemon-dill butter up to 1 week ahead and refrigerate, or freeze up to 2 months. Leftover cooked salmon and asparagus keep in an airtight container for 2–3 days in the refrigerator. Reheat gently at 275°F for 8–10 minutes or in a covered skillet over low heat until warmed through to avoid drying out. Add fresh lemon juice, a touch of olive oil, and capers after reheating to revive flavors.

Nutrition (per serving)

Approximate: 520 calories; 36 g fat; 4 g net carbs (6 g total carbs, 2 g fiber); 34 g protein; 720 mg sodium. Values will vary based on brands and exact sizes of fillets.