Heat the milk in the microwave until it is warm but not scalding. Add it to the stand of a mixer with the warm water, sugar and yeast. Stir and let the yeast proof for 5-10 minutes.
Add in the softened butter and egg and combine using the dough hook. Add in the flour and salt and mix together on low until the dough starts to form. Increase the speed and add flour if needed until the dough pulls clean away from the bowl.
On a floured surface add the dough and knead until the dough is smooth. Place in a large bowl with 1 teaspoon olive oil. Cover and let rise for 1-1/2 hours until it has doubled.
Punch the dough and roll out to 1/2 inch thick on a floured surface. Cut circles with a biscuit cutter. Indent the middle of each dough round and brush with butter. Fold in half and place in a 9x13 inch greased pan. Cover and let rise for 1 hour until doubled.
Preheat the oven to 350 degrees and bake for 15-20 minutes or until golden brown. Remove and brush with additional butter and top with flaky salt if desired.