Preheat and Prep: Preheat your oven to 200°C (180°C fan). Pat the salmon fillets completely dry with a paper towel. This is a crucial step I never skip, as it helps the skin get a little crisp and allows the seasoning to adhere properly.

Season the Salmon: Place the salmon fillets in a baking dish. Drizzle with olive oil and season generously on all sides with salt and freshly ground black pepper.

Bake the Salmon: Place the baking dish in the preheated oven and bake for 12-15 minutes. The exact time will depend on the thickness of your fillets. The salmon is done when it’s opaque and flakes easily with a fork.

Start the Sauce: While the salmon is baking, melt 2 tablespoons of the butter in a small saucepan over medium heat. Add the minced garlic and sauté for about 1 minute until fragrant. Be careful not to let it brown.

Deglaze the Pan: If using, pour in the white wine or vegetable stock to deglaze the pan, scraping up any bits from the bottom. Let it simmer and reduce by about half, which takes 2-3 minutes.

Create the Emulsion: Reduce the heat to low. Add the fresh lemon juice. Now, start adding the remaining cubes of cold butter, one or two at a time, whisking constantly. What works best for me is to keep the pan moving. Wait until each addition is almost fully melted before adding the next. This process creates a smooth, creamy sauce that won't separate.

Finish the Sauce: Once all the butter is incorporated, remove the saucepan from the heat. Stir in the chopped fresh parsley and season with a pinch of salt and pepper to taste.

Serve Immediately: By now, your salmon should be perfectly cooked. Carefully remove it from the oven. Place a salmon fillet on each plate and pour the warm lemon butter sauce generously over the top. Garnish with fresh lemon slices and serve right away.