Preheat oven to 350F (175C) and adjust oven rack to middle position. Line two aluminum half sheet pans with parchment paper
Combine sugar, baking soda, cinnamon, both gingers, vanilla, pepper, butter, and molasses in the bowl of a stand mixer fitted with the paddle attachment. Mix on low to moisten, then increase to medium, beat until fluffy, pale, tan, and soft - about 5 minutes. Add egg and beat until smooth, about 2 more minutes, pausing to scrape as needed.
Resume mixing on low, sprinkle in flour, and continue until a soft dough is formed
Divide into 48 level 1/2 oz portion with a 1 tbsp scoop. Roll smooth and round, tumble in a dish with raw or granulated sugar, and arrange on prepared sheet pans, leaving 2 inches in between. Don't flatten - these cookies will spread on their own
Bake until puffed and chestnut brown, about 22 minutes. Cool directly on sheet pan for 2 hours - prior to that, gingersnaps won't be crisp on the inside. Store leftovers in airtight container up to 3 weeks at room temperature