Make the chia pudding: In a medium bowl, whisk together 1 cup Greek yogurt, ⅔ cup milk, 2½ tablespoons honey, 2 teaspoons lime zest, 2 tablespoons lime juice, and 1 teaspoon vanilla extract until smooth. Add 4 tablespoons chia seeds and whisk well until evenly distributed. Cover and refrigerate for at least 4 hours, preferably overnight.
Make the Key Lime Pie Crumble: In a small bowl, stir together 6 tablespoons crushed graham crackers, 3 tablespoon shredded coconut, and ½ teaspoon lime zest.
Assemble: Divide about one-third of the crumble between two jars or bowls. Spoon the chia pudding on top. Sprinkle over the remaining crumble. Serve cold.
