Remove seeds and pulp from the pumpkin, dice into bite-sized pieces. Place in a microwave-safe container, add 1 tbsp water, cover loosely with plastic wrap, and microwave at 600W for 5 minutes until soft. Drain water and season with salt and pepper while mashing the pumpkin. Let cool.

Place raisins in another microwave-safe container, add enough water to cover them, and microwave at 600W for 30 seconds. Let cool with the wrap still on, then drain and pat dry with a paper towel.

Mix the cooled pumpkin with raisins, yogurt, and mayonnaise until well combined.