Preheat and prep: Heat the oven to 400°F (200°C).
Line a baking sheet with foil or parchment for easy cleanup. Pat the salmon dry with paper towels.
Season the salmon: Place the fillets on the sheet, skin-side down if using skin-on. Sprinkle with salt and pepper on top and sides.
Make the glaze: In a small bowl, whisk together fig jam, balsamic vinegar, Dijon, garlic, olive oil, a pinch of salt, pepper, and red pepper flakes if using.
It should be glossy and spoonable.
Brush generously: Spoon or brush the glaze over each fillet, coating the tops and sides. Reserve a tablespoon or two for finishing, if you like extra gloss.
Bake: Cook for 10–12 minutes, depending on thickness. A general rule is about 4–6 minutes per 1/2 inch of thickness.
The salmon should flake easily but still be slightly translucent in the center.
Optional broil: For a light char and stickier finish, switch the oven to broil for 1–2 minutes at the end. Watch closely to avoid burning the sugars in the glaze.
Finish with lemon: Squeeze fresh lemon over the salmon right out of the oven. Brush with the reserved glaze, if desired.
Top with chopped herbs.
Serve: Plate with roasted vegetables, grains, or a crisp salad. Spoon any pan juices over the top.