PREHEAT oven to 350°F.
MELT ghee in a large saucepan over medium heat. Add diced onion, celery, and garlic. Cook until onion is translucent, about 7-8 minutes.
WHISK together chicken broth, coconut milk, starch, salt and pepper.
ADD broth mixture to the sauteed vegetables. Cook for 3-4 minutes until sauce thickens, stirring regularly. This combination will be thick.
BLEND the sauce in a blender or food processor until smooth. The vegetables should be fully blended into a creamy sauce.
COMBINE in a large 9x13 casserole dish the frozen hash browns, ham, and peas. Top with blended sauce and stir until well combined.
SPRINKLE top of the casserole with the nutritional yeast. In a small bowl, combine with a fork the almond flour with the melted ghee to create the topping. This topping will not be crumbly, more of a paste, but do your best to crumble small pieces of it over the top of the casserole.
BAKE uncovered for 1 hour, until the topping is brown and potatoes are tender. Cool on the counter for 10 minutes before serving.