In your blender, add the 2 cups of frozen spinach, 1 cup of frozen pineapple chunks, 1 cup of frozen mango chunks, 1 medium ripe banana, and any optional berries you desire.
Pour in 1 cup of your choice of milk. This can be cow's milk or any plant-based alternative like almond or coconut milk.
Add 1 teaspoon of vanilla extract for flavor and sweeten to taste with your preferred sweetener. Start with a little and adjust according to your taste preference.
Blend all the ingredients on high speed until smooth and creamy. You might need to stop and scrape down the sides to ensure everything blends evenly.
Once blended to your desired consistency, pour the smoothie into a glass or a mason jar, and enjoy immediately!