In a bowl, add mayonnaise to taste and mix in some of the escabeche (pickling liquid) from the mussels. Add the liquid gradually until you reach your preferred flavor. Stir until the escabeche is fully blended in—the mayonnaise will turn a bright pink color.

Once the potatoes are done, take them out of the microwave and let them cool to room temperature before handling. Trim them as mentioned earlier so they're all the same size, and arrange them on a serving platter. Save any scraps for another time.

If you're serving the pintxos soon, spoon some of the escabeche mayonnaise onto each potato. Sprinkle paprika on top (a fine-mesh strainer helps distribute it evenly). Place a mussel on each potato and secure with a toothpick.

Finally, decorate the platter with a few sprigs of fresh thyme for presentation. Thyme is a classic herb used in escabeche for its aroma.