Preheat the oven to 425 degrees. Line a baking sheet with foil. Add a tbsp of olive oil to the bottom of it. Place the salmon fillet skin side down. Brush the salmon with the achiote marinade. Let sit for 15 minutes.
Right before throwing in the oven, brush on another layer of the marinade. Cook for 12 minutes.
While the salmon is roasting, add the rest of the marinade to a saucepan. Cook over medium heat for a couple of minutes.
The sauce should’ve thickened significantly.
Let the salmon sit for 5-10 minutes before serving.
Serve the salmon as is with black beans...or, serve it the way I did; as a double corn tortilla. taco, topped with pickled red onion, habanero pickled jalapeños, cabbage, and the thickened achiote sauce.