01 - In a large bowl, combine flour, instant dry yeast, sugar, and salt. Add warm milk and olive oil. Mix until a soft dough forms.
02 - Knead the dough for 5 to 6 minutes until smooth and elastic. Place in a greased bowl, cover, and let rise in a warm place for 45 minutes or until doubled in size.
03 - Preheat oven to 375°F. Line a baking sheet with parchment paper.
04 - In a medium bowl, combine grated cheddar cheese, red bell pepper, spinach, red onion, parsley, dried oregano, black pepper, and salt. Mix well and set aside.
05 - Punch down the risen dough and roll it out on a lightly floured surface into a rectangle approximately 1/4 inch thick.
06 - Evenly spread the filling over the dough, leaving a 1/2-inch border along all edges.
07 - Starting from the long edge, roll the dough tightly into a log. Slice into 8 equal pieces.
08 - Place rolls cut-side up on the prepared baking sheet. Brush with melted butter and sprinkle with sesame seeds if using.
09 - Bake for 22 to 25 minutes until golden brown. Allow to cool slightly before serving.