1. Preheat the oven to 400F.
2. In a medium pan preheated over medium heat, add the olive oil and garlic. Cook for 1 min until fragrant, then add the spinach with a sprinkle of salt and pepper. Cook until the spinach is fully wilted, 1-2 mins.
3. Transfer the spinach into a medium bowl and add the ricotta and a sprinkle of salt and pepper. Mix, taste, and add more salt and pepper if you like.
4. Using a paring knife, cut five oval-shaped holes (~3 x 2 inches each) in the baguette, leaving space between them. Remove the bread from each cutout to create openings. (Save the removed bread for croutons or enjoy it with butter!) Gently pull out a bit more of the soft interior to further hollow out the holes. If the baguette is too long to fit on your sheet pan, cut it in half crosswise between two of the holes to create two smaller pieces.
5. Spoon ~2 Tbsp of the spinach and ricotta filling into each hole, spreading it along the bottom and sides to create a lining. Crack an egg into each hole, then season with salt and pepper. Finish with a generous sprinkle of grated Parmesan cheese.
6. Bake until the egg white is opaque and no longer jiggles and the yolks are jammy (slightly runny), 18 to 20 mins. Let cool for 5 mins, slice in between the holes, and enjoy!
