Make the sponge: In a large mixing bowl, mix together 1 1/2 cups flour, 3/4 whole wheat pastry flour, 1 1/2 cups warm water and 1/2 teaspoon yeast until well blended. Cover the bowl and let rest overnight on the counter.
Make the dough: In the bowl of a stand mixer using the paddle attachment, combine sponge that has rested overnight, warm water, whole wheat pastry flour, salt and yeast. Mix on low speed for two minutes. Switch to the dough hook and mix in 2 cups all purpose flour a little at a time, add enough of the remaining flour as needed to make a soft, sticky dough. Knead the dough for 5 minutes. Place in a greased bowl, turning to grease top. Cover; let rise in warm place until double, about 1 hour.
Punch down dough. Cover and let rest 10 minutes.
On a floured surface, roll the dough into a 9x12-inch rectangle. Use a pizza cutter to cut the dough in three rows, each 3x12-inches. Cut each row into four 3-inch squares.
Place rolls on two non-rimmed baking sheets lined with parchment paper. Cover with plastic wrapped sprayed with non-stick spray. Let rise until the rolls have risen and indentation remains if you lightly touch a roll, about 30 minutes.
Preheat oven to 450°F. Put a pizza stone in the oven to heat while rolls are rising.
Slide parchment paper with 6 rolls on to preheated pizza stone and bake for 10 to 12 minutes until rolls are golden brown. Remove to a wire rack to cool completely before eating. Repeat with remaining 6 rolls.