We always have a green smoothie for breakfast. I know smoothies are popular, but most smoothies have milk or yogurt in them and, typically, no greens.
My usual breakfast smoothies has spinach, dandelion greens, or parsley. I also add frozen berries. You can uses any greens or fruit you desire. In fact, greens need to be rotated to avoid alkaloid build up. I prefer the lowest sugar content possible, so I use mixed berries (blackberries, raspberries, and blueberries). But you could use mango, banana, apples, peaches, etc. I also add a raw protein powder and sometimes chia seeds and raw Maca powder.
I fill my blender completely with greens. I add about 2-3 cups of water and I blend.
I add about 2 cups of frozen mixed berries and blend again.
Then I add protein powder. You can add any protein powder you like. I recommend a good plant based protein. I like using a raw protein powder. This one is from Garden of Life, but there are many other options. I use some unsweetened and some sweetened with stevia in the same smoothie. This recipe makes enough to share with my kids and they like it a little bit sweetened.
Enjoy! If you are making green smoothies for the first time, you may want to start with fewer greens and more fruit until you develop a taste for the greens. Better to start the journey simple and build up than to give up altogether from changing too much too soon!
If you are interested in more information about green smoothies, I highly recommend you read Green For Life by Victoria Boutenko.