Weigh all the ingredients.
In a measuring jug, mix lukewarm water, sour cream and oil. Stir until the sour cream is liquifies.
In a stand mixer with a dough hook, add flour, sugar and yeast then mix. After Add salt and mix.
Pour in the liquid ingredients, knead on low speed (between level 1 and 2) for 2 minutes. Let the dough rest for 10 minutes.
Knead for 2 minutes on medium-high speed (3 to 4). Let the dough rest for 10 minutes.
Knead for 4 minutes on medium-high speed (3 to 4).
Add extra 25g of bread flour, then knead on high speed (4 to 5) for 2 to 3 minutes. Start slow first to incorporate the flour.
Transfer the dough into a greased bowl (with oil), cover. Let the it rise for 1 hour or until it doubles in size.
Coat a loaf tin with butter and flour.
Roll and fold the dough to form a loaf shape. Let it proof for 30 minutes.
Preheat oven to 190℃.
Bake for 30 to 35 minutes or until golden brown.