1. Combine apples, zest, juice, cardamom, cinnamon, and salt in a food processor and whirl until smoothly puréed, 3 to 5 minutes, scraping down sides of bowl if necessary. (Bits of peel will be visible.)
2. Divide among 4 bowls. Top each serving with a dollop of yogurt and some pecans.
Note: Nutritional analysis is per 1/2-cup serving.