Whisk 3 cups soy milk, ¾ cup chia seeds, ¼ cup cocoa, ⅛ teaspoon salt, 2 tablespoons maple syrup and 1 teaspoon vanilla in a large bowl until well combined. Cover and refrigerate until thickened, at least 12 hours.
Combine ¾ cup yogurt, ⅓ cup peanut butter and the remaining 1 teaspoon maple syrup and ½ teaspoon vanilla in a small bowl; stir until smooth. Cover and refrigerate until ready to use.
Stir the chilled chia mixture; divide evenly among 4 jars or small bowls (about 1 cup each). Stir the peanut butter mixture until smooth, if needed, and spread evenly (about ¼ cup each) over the chia mixture. Dust with additional cocoa powder, if desired.
