1/3 cup each spinach, red cabbage and butternut squash juice, plus extra if needed*
3 cups all-purpose flour, divided
2 tsp kosher salt, divided
Flour and cornstarch for dusting
*
In 3 small bowls, each add 1 cup flour, a heaping 1/2 teaspoon kosher salt and 1/3 cup vegetable juice.
Working with one piece at a time, on a lightly floured surface, use a rolling pin to roll the dough into a rectangle about 1/2 inch thick and no wider than your pasta roller.
Now thin the dough by rolling it through the rollers twice at the second-widest setting and twice more at the third setting, until the dough is a little more than 1/16 inch thick (I used the first 3 settings but if you want it extra thin, you can go once through the 4th setting).