Position a rack in the middle of the oven and heat the oven to 350°F. Line a large baking sheet with parchment.
In a medium bowl, whisk together the flour, rosemary, baking powder, sugar, baking soda, and salt. Using your fingers, disperse the butter evenly in the flour mixture until it resembles coarse meal. Add the cream and stir with your fingers until a soft, tacky dough forms. Form the dough into a square, wrap in plastic wrap, and chill until slightly firm, about 15 minutes.
On a well-floured surface, roll the dough into a rectangle approximately 5x13 inches, and cut it crosswise into 1/2-inch strips (you will have about 26 strips). Working with one strip at a time, twist repeatedly (without pulling) into a tight spiral and place on the parchment-lined baking sheet, spaced about 1 inch apart.
Bake until the bottoms of the twists are brown, about 7 minutes, then carefully turn over and bake until brown all over, about 3 minutes more. Cool the grissini on the parchment on a rack.
Make Ahead Tips
The grissini can be stored in an airtight container for up to 5 days.
Photo: Scott Phillips