Combine the unsweetened almond milk, strawberries, and vanilla extract in a blender or Nutribullet and blend until smooth. Pour the mixture into a bowl or jar, then stir in the chia seeds.
Let it sit for 5 minutes, then stir again to prevent clumping.
Cover and refrigerate for at least 2 hours, or overnight, until thickened.
(Optional: add 1/2 to 1 teaspoon monk fruit sweetener or Stevia)