1.   Add the frozen butter cubes and pulse until none of the butter is larger than the size of a pea.

2.   Cut butter cubes into flour until mixture is crumbly and pieces are pea-size.

3.   Place half the butter cubes in freezer.

4.   Scatter the butter cubes over the flour mixture.

5.   Using an immersion blender, whip mixture, adding frozen butter cubes gradually.

6.   Using an immersion blender, whip the mixture, adding frozen butter cubes gradually.

7.   Whisk in butter cubes one at a time until incorporated.