Preheat oven to 375°F. Make gravy and set aside.
In sauté pan on medium heat, add oil and heat until shimmering. Then add onion and garlic and cook until softened, about 3-4 minutes.
Add spinach and then season with salt and pepper to taste. Cook until spinach has thawed and given off most of its liquid, about 4-5 minutes.
Prepare gravy according to back of package. Add gravy, 1 cup mozzarella cheese (½ cup cheese will used later), and artichokes. Stir until combined and cheese has melted. Check seasoning and adjust if necessary. Set aside.
Create a long pocket along the top, lengthwise by cutting the center of the French Batard all along the top from end to end, being careful not to cut all the way down. It will look like a really large hotdog bun.
Then create a score in the middle of the bread, perpendicular to the long pocket, being careful not to cut all the way down to keep the entire loaf from separating. Then create a similar cut on either side of the score in the middle, which will create 4 “portions” of the bread without dividing the bread entirely.
Open up the center of the bread and spread the entire spinach and artichoke mixture all along the long pocket of the bread.
Place remaining ½ cup mozzarella cheese on top of spinach and artichoke mixture and place bread on a sheet tray. Place sheet tray in 375°Foven and bake until cheese has started to brown, about 4-5 minutes.
Serve warm and divide along the pre-cut scores.
