In the bowl of a stand mixer, combine the flour, yeast, and salt. Add the warm milk, honey, the egg, and butter. Using the dough hook, mix until the flour is completely incorporated, about 4-5 minutes. If the dough seems sticky, add the remaining 1/4 cup of flour. Cover the bowl with plastic wrap and let sit at room temperature for 15 minutes or up to a few hours at room temperature. To make the honey butter. Combine the butter and honey together in a small bowl. Preheat the oven to 350 degrees F. Grease a 9x13 inch baking dish.Lightly dust your work surface with flour. Turn out the dough, punch it down, and divide the dough in half. Roll each half to a 12-inch square, about 1/4-inch thick. Brush each square with honey butter, saving any leftover butter for serving. Cut each square of dough into 6 strips. Roll each strip into a coil (see above photo) and arrange seam side down in the prepared baking dish. Cover the dish and let the rolls rise for about 30 minutes, until they're puffy. Alternately, you can let the rolls sit in the fridge overnight.Bake the rolls for 18-25 minutes, until they're golden brown. Remove them from the oven and brush with the remaining honey butter. Pull them apart to serve warm with flaky sea salt.