Ingredients

6 cups all-purpose flour 

1/4 cup baking powder 

1 teaspoon baking soda 

1/4 cup sugar 

2 teaspoons salt 

2 cups solid vegetable shortening, or 1 cup each unsalted butter (2 sticks) and shortening 

1/4 cup finely chopped mixed herbs, such as chives, dill, and thyme 

1 1/4 cups buttermilk 

1/4 cup heavy cream 

Preparation

Preheat oven to 400 degrees. In a large bowl, whisk together 4 cups flour, baking powder, baking soda, sugar, and salt. Using a pastry cutter, cut shortening into dry ingredients until texture resembles rolled oats. Add herbs and remaining 2 cups flour; gently toss to combine. Cover with plastic wrap, and chill in refrigerator for at least 20 minutes.

Make a well in center of chilled mixture. Pour in buttermilk, and stir in quickly with your hands or a large spoon until just combined. It does not matter if there are bits of unincorporated flour left in the bowl.

Turn mixture out onto a lightly floured work surface, and divide in two. Shape dough lightly into rough rectangles. Place one piece on top of the other. Transfer right onto a nonstick baking mat-lined baking sheet, preferably without sides. Roll dough out quickly and gently, being careful to not overwork dough. Pat edges to make them straight. Cut into 2-inch square pieces.

Brush tops with heavy cream. Bake until golden, 20 to 25 minutes; cover with parchment paper-lined foil if browning too quickly. Place sheets on wire racks to cool.