Whole Wheat Flour (Best Option)
1:1 (1 tablespoon whole wheat flour per 1 tablespoon all-purpose flour)Whole wheat flour contains similar gluten and starch content to all-purpose flour, allowing it to thicken the gravy effectively while providing a more robust flavor profile that complements the meat and vegetables in Shepherd's Pie.
When using whole wheat flour, whisk it thoroughly to avoid clumping and cook it slightly longer to reduce any raw flour taste. Because it absorbs more liquid, monitor the consistency and adjust liquids if necessary.
The final gravy will be slightly heartier and darker, enhancing the rustic character of the dish without compromising the traditional texture.