Preheat oven to 350°F (175°C).

Slice the French bread into 1-inch thick pieces, being careful not to cut all the way through the bottom crust.

Place a slice of mozzarella cheese between each slice of bread.

Place the bread on a sheet of tinfoil.

Melt the butter.

Chop the onion and parsley.

In a bowl, combine the melted butter, chopped onion, parsley, and poppy seeds.

Pour the butter mixture over the bread, ensuring it seeps between the slices.

Bake in the preheated oven for 20 minutes, or until the top is crispy and the cheese is melted and bubbly.

Sprinkle with paprika before serving.

Serve immediately.