Mix the spices, Italian seasoning through red chili flakes in a bowl. Coat the beef round with the spice mix evenly. Wrap tightly in plastic wrap and refrigerate for at least 3 hours to overnight.
When ready to cook, preheat the oven to 275.
In a braiser, heat the bacon fat over medium high heat and brown beef on all sides, about 15 minutes total. Add the onions and cook for another 5 minutes, until tender. Add the garlic and cook one minute longer. Finally, add the wine, Worcestershire, beef stock, and bay leaves. Deglaze the pan and transfer to oven to finish cooking.
Cook for 1 hour 30 minutes, uncovered.
Remove meat from cooking liquids and let cool completely. (After a 20 minute cool, I wrap tightly in aluminum foil and cool in fridge for easy slicing).
When the meat is cool, slice into very thin pieces. Reheat the broth and add the beef.
Assemble the sandwich by layering meat, with extra broth, giardiniera and red pepper strips over the toasted rolls. If it’s not messy, you didn’t do it right.