In a large bowl, dissolve yeast and sugar in warm water (around 110°F/45°C). Let sit for 5 minutes.
Add flour, salt, and melted butter. Mix until combined.
Knead dough on a floured surface for ~8 minutes until smooth and elastic.
Place in a greased bowl, cover, and let rise in a warm place for 1 hour.
Punch down the dough, shape into a loaf, and place in a greased 9x5-inch loaf pan.
Cover and let rise for another 30 minutes.
Preheat oven to 375°F (190°C). Bake for 25-30 minutes until golden brown and hollow-sounding when tapped.
Cool in the pan for 10 minutes, then transfer to a wire rack.
Notes
Adjust water gradually if the dough is too dry; add flour if sticky.
For best flavor, let the loaf cool completely before slicing.
Store in an airtight container for up to 3 days or freeze for 1 month.