For the Cookies:
Preheat oven to 375F and line two baking sheets with parchment paper.
In a medium bowl, whisk together the flour, baking soda, cinnamon, ginger, cloves, allspice, pepper and salt. Set aside.
In a large bowl, beat the butter with the brown sugar and granulated sugar until light and fluffy, about 4 minutes. Beat in the egg yolk and vanilla until combined. Beat in the molasses until fully incorporated, scraping down the beaters and the sides of the bowl as needed.
With mixer on low, slowly add the flour mixture until fully combined, about 30 seconds.
Roll the dough into 1-inch balls and place on prepared baking sheets, leaving 2 inches between them. They will spread a lot. Bake one sheet at a time until cookies are beginning to set around edges and tops are cracked but still puffy and soft, about 10 minutes. They will seem underdone in the center, this is how you want them.
Let cool on baking sheet for 10 to 15 minutes and then transfer to a wire rack to cool completely.
For the White Chocolate Dip:
Line a baking sheet with parchment or waxed paper. Set a medium bowl over a pan of barely simmering water (don’t let the bowl touch the water). Add white chocolate chips and vegetable oil and stir until chocolate is melted and smooth.
Dip each cookie halfway into white chocolate mixture. Tap cookie lightly to remove excess chocolate, then place on parchment-lined baking sheet. Sprinkle with your choice of holiday sprinkles. Repeat with remaining cookies. Refrigerate until white chocolate is firm, about 20 minutes.