Instructions 

1. In a large pot set over medium-high heat, add the oil, butter, and onion. Cook until the onion is translucent. Then add the celery and carrots, cook for about 3 minutes.
2. Then add the ground venison, salt and pepper. Cook until the meat in cooked through.
3. Add the milk, nutmeg, and wine to the pot. Cook for about 5 minutes, then add the tomatoes.
4. Let the sauce simmer on low uncovered for about 1 hour.
5. Preheat an oven to 400F.
6. Take a large cast iron skillet, use a pastry brush to brush 3 tablespoons of olive oil all around the inside of the pan, add the pizza dough to the pan making sure that there is about 1/2 inch of the dough going up the sides around the pan. Then add about 1-1/2 cups of the Bolognese sauce to the top of the pizza dough. The dollop the cream fraiche on top of the sauce. And sprinkle the fresh basil leaves on top.
7. Bake the pizza for about 18-20 minutes.
8. While pizza is hot drizzle chili oil to your liking on top, then serve.