Place the prunes in a bowl and cover them with warm water. Set aside to soak for 30 minutes.
Meanwhile, grate the orange peel until you have ½ teaspoon of orange zest.
Peel the orange and chop the segments from half of the orange. Reserve the other half for another use.
Drain the prunes and place them in a small saucepan with the orange zest, chopped orange segments, and ½ cup water.
Bring the mixture to a boil and then immediately lower to a simmer. Let simmer, stirring occasionally, for about 5 minutes until thickened, mashing with a fork at the end to break up large pieces.
Remove from the heat and stir in the chia seeds.
Transfer the mixture to a jar and set it aside, uncovered, until cool and thickened, at least 2 hours.
Serve as desired. Store in the refrigerator for up to 5-7 days.