HEAT TREAT FLOUR: You can heat treat flour in the microwave or in the oven. Test the flour to ensure it's reached a safe temperature of 165 degrees F. Let flour cool COMPLETELY to room temperature before using. Don't use any burnt or clumpy flour (if it's off-color or smells burnt, it is burnt). The flour should be light, white, and fluffy. Spoon the cooled flour into a measuring cup and level the top of the measuring cup with the back of a table knife. (See note 1.)
DRY INGREDIENTS: Add the spooned and leveled 1 and 1/4 cups flour, 1/2 teaspoon salt, and 1/2 teaspoon baking soda to a medium-size bowl and stir. (While we aren't baking this dough, the baking soda gives it an authentic cookie dough flavor; leave it out if desired, just don't forget the salt!)
WET INGREDIENTS: In a large bowl with a stand mixer (or use a hand mixer), add beat 8 tablespoons room temperature (not melted) butter and 3/4 cup peanut butter. Beat until very smooth and creamy, about 2-3 minutes. Add the 1/4 cup white sugar and 1/2 cup + 2 tablespoons brown sugar and beat to combine. Beat for an additional 3-4 minutes or until mixture becomes light, smooth, and fluffy. Add the 2 tablespoons heavy cream and 1 teaspoon vanilla and mix until combined.
COMBINE: Add the dry ingredients to the wet ingredients. Beat until just combined; do not over-mix. Use a spatula to scrape the sides of the bowl as needed. If the dough is at all dry, add in a bit more heavy cream; if it is wet, add in a tablespoon or two more of the heat-treated flour.
ENJOY: Stir in any of desired mix-ins and enjoy! We love this dough freshly made, chilled, or even frozen!