In a large skillet, heat the oil over medium-high heat. Working in batches, add the ribs and cook, turning often, until browned, 7 to 10 minutes. Transfer to a seared ribs to a large slow cooker.
Add the onion and garlic to skillet and cook, scraping up any browned bits, until slightly softened, about 4 minutes.
Stir in the wine and tomatoes and bring to a boil. Transfer the mixture to the slow cooker with the short ribs and cook on low heat until tender, about 6 hours.
Prepare the gravy sauce:
Remove ribs from slow cooker and shred. Set aside ½ of the shredded rib meat to use on the pizza and store the remaining half for future use.
Strain the cooking liquid into a large measuring cup. Transfer liquid to a saucepan and discard solids.
Bring broth to a boil on high, then reduce heat to a simmer.
Whisk in the tomato paste and season with salt and pepper.
In a small bowl, Whisk together 1 teaspoon arrowroot powder with ¼ cup water. Add to broth and cook until slightly thickened.
Set aside ½ of the sauce to top the pizza, reserving the other half for future use.
Prepare the pizza crust
Preheat oven to 450 degrees.
Follow instructions to make low carb pizza dough.
Place parchment paper on large cookie sheet and spritz with cooking spray.. Place pizza dough on parchment paper and roll out thin. Poke holes in crust with tines of fork and bake for 10 minutes.
Assemble and bake:
Remove crust from oven and spoon a thin layer of gravy over top of pizza crust. Store any remaining gravy in the fridge up to 5 days.
Top gravy with mozzarella cheese, havarti cheese and 2 cups shredded short ribs.
Return to oven and bake another 10 minutes, until cheese is melted.
Remove from oven and let cool 10 minutes. Top with arugula.