Preheat your Traeger grill to 350*
Place the cedar plank in the baking dish and submerge in room temperature water
Allow the plank to soak while the grill heats up
Remove the cedar plank from the water
Place the salmon, skin side down, on the soaked plank
Season it liberally with the rub
Place the plank and salmon in the center of the Traeger and close the lid
While the salmon cooks, make the salsa
Cut the peaches in half, remove the pit, and dice into ¼ inch cubes
Chop the red onion into fine dice
Chop the cilantro roughly
Smash the garlic cloves
Slice the green onion thinly
Dice the serrano and taste to determine spiciness (use less than ½ a pepper total)
Combine all these ingredients in a bowl
Stir in the oil and vinegar and toss to combine
Season the salsa with salt and pepper to taste
Cook the salmon until the internal temperature reaches 130*
Pull the plank and salmon from the grill and serve with the peach-serrano salsa