In a small bowl, combine the warm water and active dry yeast. Stir gently and let it sit for about 5 to 10 minutes, or until it becomes frothy.
In a large mixing bowl, whisk together the bread flour and sea salt. Make a well in the center and pour in the frothy yeast mixture along with the melted butter and olive oil. Add the chopped rosemary to the mix.
Using a wooden spoon or your hands, mix the ingredients until they form a shaggy dough. If too sticky, add more flour, one tablespoon at a time, until it holds together.
Transfer the dough to a lightly floured surface and knead for about 5 to 7 minutes until smooth and elastic. Add flour if too sticky.
Place the kneaded dough into a greased bowl and cover with a kitchen towel. Let rise in a warm place for 1 to 1.5 hours, or until doubled in size.
Punch down the dough gently to release air. Divide into 12 to 15 equal pieces. Shape each piece into a ball and place on a greased baking sheet with space between.
Cover the rolls with a towel and let rise for another 30 to 45 minutes until puffed up.
Preheat oven to 375°F (190°C) while rolls rise.
Bake the rolls for 20 to 25 minutes until golden brown and hollow sounding when tapped on the bottom.
Remove rolls from oven and cool on a wire rack for a few minutes. Serve warm, optionally drizzled with more olive oil.