In the bowl of a stand mixer or in a large bowl by hand, combine the warm water, yeast, sugar, oil, salt and 2 cups of the flour (if you are using active dry yeast instead of instant yeast, let the yeast proof in the warm water and sugar for about 3-5 minutes until it is foamy and bubbly before adding the oil, salt and flour). Begin mixing and continue to add the rest of the flour gradually until the dough pulls away from the sides of the bowl. (You may not need to use all of the flour the recipe calls for) The dough should be soft and smooth but still slightly tacky to the touch.
Knead dough in the stand mixer or by hand until it is very smooth and elastic, about 5 minutes in a stand mixer or 8-10 minutes by hand. Lightly spray a large bowl with cooking spray and place the dough in the bowl. Cover the bowl with lightly greased plastic wrap. Let the dough rise until it has doubled (about 45 minutes to an hour).
Punch down dough and turn it out onto a lightly greased countertop. Divide the dough into 12 equal pieces and form the dough into round balls. Place the rolls on a lightly greased or silpat-lined baking sheet about an inch or two apart. Cover rolls with a kitchen towel or lightly greased plastic wrap. Let rolls rise until doubled.
Preheat oven to 400° F. Bake for 12-14 minutes until lightly browned and cooked through. Remove from oven and immediately rub the tops of rolls with butter.