In a medium bowl, combine warm water with yeast and a pinch of sugar. Allow to foam for 5-10 minutes.

In a large mixing bowl, whisk together all-purpose flour and salt. Create a well, add yeast mixture and olive oil. Stir until a soft dough forms.

Knead for 5-7 minutes until smooth and elastic. Cover and let rise for 1 hour.

Heat olive oil in a large skillet over low heat. Add sliced onions and cook gently for 20-30 minutes until caramelized.

Add fresh spinach and cook until wilted, then mix in nutritional yeast, salt, and pepper to taste.

Punch down dough and roll out into a rectangle about ¼ inch thick.

Spread filling over the dough, roll tightly, and slice into 1 to 1.5-inch pieces.

Arrange rolls in a greased baking dish and let rest for 20 minutes.

Preheat oven to 375°F (190°C). Bake rolls for 25-30 minutes until puffed and golden brown.