the flour all at once. stir the mixture vigorously until it forms a smooth ball and leaves a thin film on the bottom of the pot, about 2 to 3 minutes.
transfer the hot flour mixture to the work bowl of a stand mixer. allow the mixture to cool to 140 f, about 5 minutes. once cooled beat the mixture with the paddle attachment and add the eggs one at a time, not adding the next until the first is completely combined. the mixture should be glossy and the consistency of very thick cake batter.
transfer the mixture to a piping bag with a wide tip (i used a 1a tub. pipe 