4-5 oranges, peeled (or 1 cup high quality low-pulp orange juice if you don't care for the)
1 can mandarin oranges in light syrup (I used the 11 ounce can as well as the liquid)
1/4 cup triple sec (depending on how sweet the oranges are, you may need to decrease this)
1/2 cup tequila (you could easily increase this to 1 cup)
1/2 lime, including peel
2 Generous handfuls baby spinach
2 Cups ice (for blending)
ice to fill glasses
Throw everything, except ice, in the blender in the order listed.
Blend on high until liquid is a consistent color -- and you cannot see bits of lime peel or spinach.
Turn blender off. Add ice and continue blending until smooth.
Pour into ice-filled margarita glasses.