Maple-Mustard Glazed Salmon with Apples and Onions

Why You’ll Love This Recipe

• Effortless sheet-pan dinner with elegant, restaurant-quality flavors.
• Sweet-tart apples and caramelized onions balance a glossy maple-mustard glaze.
• Crunchy toasted walnuts add texture and richness without extra fuss.
• Ready in 40 minutes with simple ingredients you likely have on hand.

Grocery List

• Produce: 2 crisp apples (Honeycrisp or Pink Lady), 1 large yellow onion, fresh thyme, flat-leaf parsley (optional)
• Dairy: None
• Pantry: Salmon fillets, pure maple syrup, Dijon mustard, whole-grain mustard, olive oil, apple cider vinegar, walnuts, kosher salt, black pepper

Full Ingredients

For the Apple-Onion Bed

• 2 medium apples (about 1 lb total), cored and thinly sliced (about 1/4 inch)
• 1 large yellow onion (about 10 oz), thinly sliced (about 1/4 inch)
• 1 tbsp olive oil
• 1/4 tsp kosher salt
• 1/8 tsp freshly ground black pepper

For the Maple-Mustard Glaze

• 3 tbsp pure maple syrup
• 2 tbsp Dijon mustard
• 1 tbsp whole-grain mustard
• 1 tbsp olive oil
• 1 tsp fresh thyme leaves (or 1/2 tsp dried thyme)
• 1/4 tsp kosher salt
• 1/4 tsp freshly ground black pepper

For the Salmon

• 4 salmon fillets, 5–6 oz each (skin-on or skinless), patted dry
• 1/4 tsp kosher salt
• 1/8 tsp freshly ground black pepper

For Finishing

• 1/3 cup walnuts, roughly chopped and toasted
• 2 tsp apple cider vinegar (plus more to taste)
• 2 tbsp chopped fresh parsley (optional)

Step-by-Step Instructions

Step 1: Preheat and prepare the pan

Heat oven to 400°F (205°C). Line a large rimmed sheet pan (18×13-inch) with parchment paper for easy cleanup.

Step 2: Build and pre-roast the apple-onion bed

In a large bowl, toss the sliced apples and onion with 1 tbsp olive oil, 1/4 tsp kosher salt, and 1/8 tsp pepper. Spread in an even layer on the prepared pan. Roast for 10 minutes to soften the fruit and start caramelization.

Step 3: Whisk the maple-mustard glaze

Meanwhile, in a small bowl, whisk together the maple syrup, Dijon mustard, whole-grain mustard, 1 tbsp olive oil, thyme, 1/4 tsp salt, and 1/4 tsp pepper until glossy and emulsified.

Step 4: Season and position the salmon

Pat the salmon very dry with paper towels. Season the fillets on both sides with 1/4 tsp salt and 1/8 tsp pepper. Remove the sheet pan from the oven and gently toss the apples and onions. Make four spaces and nestle the salmon on top of the apple-onion bed.

Step 5: Glaze and bake

Brush the salmon generously with about half the glaze. Return the pan to the oven and bake for 10–12 minutes, until the salmon registers 125°F (52°C) in the thickest part for medium (or to your preferred doneness). Brush with the remaining glaze. For a deeper caramelized finish, broil 1 minute, watching closely.

Step 6: Toast the walnuts

While the salmon bakes, toast the chopped walnuts in a dry skillet over medium heat, stirring, until fragrant and a shade darker, 3–4 minutes. Transfer to a plate to cool slightly.

Step 7: Finish with vinegar and serve

Remove the pan from the oven. Splash 2 tsp apple cider vinegar over the apples and onions and gently toss them with a spatula beneath the salmon. Scatter the toasted walnuts and parsley over the top. Let the salmon rest 3 minutes, then serve, spooning the saucy apples and onions onto plates and placing a fillet on each portion.

Pro Tips

• Dry fish equals better browning: pat the salmon thoroughly before glazing.
• Slice evenly: 1/4-inch apple and onion slices cook at the same rate and won’t burn.
• Mind the temp: pull salmon at 120–125°F (49–52°C) for medium to medium-rare; it will rise a few degrees as it rests.
• Line the pan: parchment prevents sticking and keeps the apples beautifully intact.
• Balance the flavors: add another 1–2 tsp cider vinegar at the end if you prefer a brighter, tangier finish.

Variations

• Pecan swap: Use chopped pecans instead of walnuts for a softer, buttery crunch.
• Sheet-pan veggies: Add 8 oz trimmed green beans around the apples and onions; toss with a drizzle of oil and roast alongside.
• Different fish: Try arctic char or steelhead trout with the same timing and glaze.

Storage & Make-Ahead

Refrigerate leftovers in an airtight container for up to 2 days. Reheat gently at 275°F (135°C) for 8–10 minutes, just until warm, or enjoy cold flaked over salad. Toast walnuts up to 3 days ahead and store at room temperature. Mix the glaze up to 4 days ahead and refrigerate; whisk before using. Slice apples and onions up to 1 day ahead and refrigerate tightly covered.

Nutrition (per serving)

Approx. 600 calories; 36 g fat (6 g sat); 29 g carbohydrates; 6 g fiber; 21 g sugars; 40 g protein; 560 mg sodium. Values are estimates and will vary by ingredients and portions.