Add maple syrup, mustard, garlic powder, & sea salt to a bowl. Combine ingredients. Place salmon in a gallon bag pour the marinade over salmon. Marinate at least an hour.
Preheat smoker to 225º. Remove salmon from fridge. Let come to room temp for 10 mins. Remove salmon from marinade & set aside. Smoke for 1 hour at 225ºF.
While salmon is smoking, prepare cream cheese spread. After an hour, brush salmon with marinade & increase temp to 375 for 10 min. Remove & let rest.
Serve immediately with the cream cheese spread Eat or place the salmon in the refrigerator to cool and serve cold.