Prepare the Florentine Spinach Spread:
* Heat olive oil in a large skillet or pan over medium heat.
* Add the minced garlic and chopped shallot (or onion). Sauté for 2-3 minutes until softened and fragrant, being careful not to burn the garlic.
* Add the fresh spinach to the skillet in batches, if necessary. Stir frequently until all the spinach is wilted down. This will happen relatively quickly, about 3-5 minutes.
* Remove the skillet from the heat. If there’s a lot of excess liquid from the spinach, carefully drain it off or use a slotted spoon to transfer the spinach mixture to a bowl, leaving the liquid behind. Squeezing out excess moisture is key to a non-soggy sandwich.
* To the wilted spinach, add the softened cream cheese, grated Parmesan cheese, ground nutmeg, salt, pepper, and red pepper flakes (if using). Stir vigorously until the cream cheese is fully melted and incorporated, creating a creamy, cohesive spinach mixture. Taste and adjust seasoning if needed. Set aside.

2. Assemble the Sandwiches:
* Lay out your 8 slices of bread on a clean work surface.
* Divide the Florentine spinach spread evenly among 4 of the bread slices, spreading it from edge to edge.
* Layer the sliced turkey evenly on top of the spinach spread on those same 4 slices. Aim for about 1/4 pound of turkey per sandwich.
* Top the turkey with 2 slices of Provolone cheese (or your cheese of choice) on each sandwich.
* Place the remaining 4 slices of bread on top to close the sandwiches.

3. Grill the Sandwiches:
* Lightly butter the outside of the top slices of each assembled sandwich.
* Heat a large griddle, non-stick skillet, or panini press over medium-low to medium heat. You don’t want the heat too high, or the bread will burn before the cheese melts and the filling heats through.
* Carefully place the sandwiches, butter-side down, onto the hot griddle or skillet. If using a skillet, you may need to cook them in batches.
* While the first side is grilling, lightly butter the now-top sides of the sandwiches.
* Grill for 4-6 minutes per side, or until the bread is golden brown and crispy, and the cheese is fully melted and gooey. If using a panini press, cook according to its instructions, usually for about 5-7 minutes.
* Press down gently with a spatula occasionally while grilling if using a skillet, to help the sandwich heat evenly and the layers meld together.

4. Serve and Enjoy:
* Once perfectly grilled, remove the sandwiches from the heat.
* Let them rest for a minute or two before slicing. This helps the melted cheese set slightly and prevents the filling from oozing out too much.
* Slice the sandwiches in half diagonally (because everyone knows diagonal tastes better!) and serve immediately