In a small bowl, combine warm water (about 105–115°F / 40–46°C) with the granulated sugar and active dry yeast. Stir gently and let sit 5–8 minutes until foamy.

In a large mixing bowl, combine the all-purpose flour and fine sea salt. Make a well in the center.

Add the foamed yeast mixture and 1 tablespoon extra-virgin olive oil to the flour. Stir with a wooden spoon until a shaggy dough forms.

Turn the dough onto a lightly floured surface and knead for 8–10 minutes until smooth, elastic, and slightly tacky. If dough is too sticky, add up to 2 tablespoons more flour; if too dry, add a teaspoon or two of water.

Lightly oil a clean bowl with remaining 1 tablespoon olive oil, place the dough inside, cover with plastic wrap or a damp towel, and let rise in a warm draft-free place for 60–75 minutes until doubled in size.

Filling & Assembly

While the dough rises, prepare the filling: in a medium bowl combine ricotta, Parmesan, shredded mozzarella, sliced basil, lemon zest, salt, and black pepper. Stir until evenly mixed. Taste and adjust seasoning if necessary.

Preheat the oven to 425°F (220°C). Line a baking sheet with parchment paper or lightly oil it.

When the dough has doubled, gently deflate it and turn it out onto a lightly floured surface. Divide into 12 equal pieces (approximately golf-ball size). Let pieces rest 5 minutes covered with a cloth so the gluten relaxes.

Working with one piece at a time, flatten each portion into a small disc (about 3–3.5 inches diameter) using your fingers or a rolling pin. Place about 1 tablespoon of the ricotta-mozzarella filling in the center of each disc.

Gather the edges of the dough up over the filling and pinch closed to form a sealed ball (bollino). Roll gently between your hands to smooth the seam and shape into a round bun. Place seam-side down on the prepared baking sheet, leaving space between each.

Beat the egg with 1 teaspoon water to make an egg wash. Brush the tops of each bollino with the egg wash for color and gloss.

Finish & Bake

Optionally, brush the tops lightly with 1 tablespoon extra-virgin olive oil and sprinkle with flaky sea salt and a pinch of chili flakes for heat.

Bake in preheated oven for 14–18 minutes, rotating the pan halfway, until the bollini are golden brown and the filling is hot and cheese is melted.

Remove from oven and transfer to a wire rack. Let cool 5 minutes before serving so the filling sets slightly.

Serve warm. These are best eaten the day they are made; reheat gently in a 325°F (160°C) oven for 6–8 minutes if needed.