Pre-heat the oven to broil.
Lay the slices of baguette, cut side down, on a baking sheet.
Brush the slices of baguette with olive oil.
Place in the pre-heated oven and broil until golden; don't walk away as the slices will burn very quickly.
Remove from the broiler.
Peel a clove of garlic and cut it in half.
Rub the cut side of the garlic all over the top of the warm toasted baguette slices; set aside.
In an 8 or 10-inch oven safe skillet, add the marinara sauce and baby spinach.
Heat the sauce, ove rmedium-high heat, stirring until the spinach wilts and the sauce is heated through.
Remove the pan from the heat and lay the slices of mozzarella over the top in a single layer.
Place the skillet in the oven and broil until the cheese is melted and bubbly; about 3 – 5 minutes.
Serve immediately with the slices of baguette.
