Sanitize all work areas, cutting boards, equipment and sinks used in the preparation of this recipe.
Melt butter in a heavy bottom pot or rondeau over medium heat, ensuring it doesn't burn.
Add flour, whisking constantly, ensuring no lumps form.
Continue whisking until thoroughly combined and smooth.
Continue to cook, stirring frequently from the bottom of the pot upward, for 5 minutes. Spread the roux in an even layer across the interior bottom surface of the pot.
Carefully transfer the pot into a preheated 350°F oven.
Cook until the roux is blond in color and its consistency resembles wet sand, about 30-45 minutes. Carefully stir the roux every 15 minutes to ensure even cooking.
Remove from the oven. Cool completely.
Transfer to clean food storage containers. Cover, label, date and store for service.
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