Preheat oven to 350 degrees F.
Use a spiralizer or a vegetable peeler to slice the zucchini into zoodles (zucchini noodles).
Chop the zoodles roughly so they aren't too long.
Place the zoodles in a colander over a bowl and sprinkle with sea salt. Let this sit for 30 minutes to sweat while you prepare the rest of the ingredients.
Place all ingredients for the cashew cream sauce in a high speed blender and blend until smooth and creamy. Set aside.
Heat avocado oil in a large skillet over medium heat.
Add onion and sauté for 3-4 minutes until fragrant.
Add mushroom and garlic with salt and pepper and cook stirring for 5 minutes until the mushroom slices are softened.
Stir in StarKist Selects E.V.O.O.® Yellowfin Tuna and break apart the meat. Remove from heat.
Wrap the zoodles in a paper or kitchen towel and squeeze out as much liquid as possible.
Stir zoodles and the cashew cream sauce into the tuna and vegetable mixture.
Transfer to a 9x9 baking dish and bake for 12-15 minutes until lightly browned.
If you'd like, you can serve with chopped parsley and/or red pepper flakes!