Preheat oven to 350°F.

In large mixing bowl, combine flour, sweetpotato, parmesan, cheddar, butter and salt. Mix with beater until mixture becomes sandy. Add milk and knead into a ball.

On floured surface, roll dough into a ¼-inch thick rectangle. Cut into ¼-inch wide strips. Gently transfer strips to a parchment paper lined cookie sheet.

Bake until ends are slightly brown, about 12 to 15 minutes. Remove from oven; cool.