Pat the salmon dry: Use paper towels to dry the fillets well. Season both sides with salt and pepper. Dry surfaces help the salmon sear and brown nicely.

Make the glaze base: In a small saucepan, combine blackberries, balsamic vinegar, honey, soy sauce, Dijon, garlic, lemon zest, lemon juice, and red pepper flakes if using. Stir to mix.

Simmer and reduce: Bring the mixture to a gentle simmer over medium heat. Cook for 6–8 minutes, stirring and lightly mashing the berries with a spoon, until the sauce is syrupy and reduced by about one-third.

Strain (optional): For a smooth, glossy finish, pour the sauce through a fine-mesh strainer into a bowl, pressing on the solids. If you like a rustic texture with seeds, skip this step.

Preheat the pan: Heat a large skillet over medium to medium-high heat. Add olive oil and swirl to coat.

Sear the salmon: Place the fillets in the pan, skin-side down if they have skin. Cook undisturbed for 4–5 minutes, until the bottom is nicely browned and the color has turned opaque about halfway up the sides.

Flip and finish: Flip the salmon and cook another 2–4 minutes, depending on thickness, until it’s just cooked through. Aim for an internal temperature of 125–130°F for medium, or to your preferred doneness.

Glaze the fish: Reduce the heat to low. Spoon about half the blackberry balsamic glaze over the salmon in the last minute of cooking, letting it bubble slightly and coat the fish.

Rest and serve: Transfer the salmon to plates. Spoon more glaze on top and garnish with fresh thyme or basil if you like. Serve immediately with your favorite sides.