HEAT OVEN to 425F/218C. Line a baking pan with parchment paper or aluminum foil sprayed with oil for easy clean up.
MARINATE THE SALMON: Put maple syrup, soy sauce, ginger, garlic and pepper in a sealed bag. Squish to blend. Add salmon. Marinate salmon for 20 minutes.
MAKE THE SALSA: Place all salsa ingredients in a bowl and mix well. Set aside.
MAKE GLAZE FROM MARINADE: Remove salmon from marinade and place it on a baking sheet lined with parchment paper or aluminum foil (spray with oil) for easy cleanup. Pour marinade from bag into a small microwavable measuring cup or bowl. Add the cornstarch and whisk to blend. Microwave for 45 seconds to thicken glaze. Pour over salmon, reserving 1 tbsp to glaze after roasting.
BAKE SALMON: Place salmon skin side down on prepared pan and bake for 8-12 minutes (depending on thickness of salmon) or until just flaky and still warm pink inside. Estimate 10 minutes per inch (2.5 cm) of thickness. Don't overdo it. Brush with remaining glaze after baking.
SERVE: Place roasted salmon on a large serving dish or individual plates. Garnish with chopped parsley and serve immediately with peach salsa on top or on the side.
