I know you said you have tried spinach in smoothies, but here is the site for anyone interested in the concept of
Green Monsters.
Also, I make protein shakes using this concept:
NOW Green Monster
Ingredients
1 scoop NOW Whey Protein Isolate Powder
1 TBS Hodgson Mill Flax Seed
2 cups Organic spinach (uncooked)
1 small banana (80g)
3/4 cup Almond or Vanilla Almond Milk (unsweetened)
ice
Combine Ingredients as ordered above in a blender for about 1.5-2 min.
YUMMINESS
You can also see a photo on my blog, just click the link below.