Make the filling
Finely chop the kale, place in a bowl and microwave on high for 20-30 seconds just to wilt it slightly.
Add the remaining ingredients and stir to combine.
Make the crepes for the tartlet shells (or skip this and use tortillas)
Put the eggs and milk in a blender and blend for a few seconds. Add the dry ingredients and blend for 10 seconds.
Drizzle in the butter with the blender on low. Cover the blender and blend on medium a few seconds more.
Heat a non-stick skillet over a high flame for 2 minutes. Brush very lightly with butter and turn the the heat to medium-high
Swirl and gently shake the skillet as you pour in the batter to spread it evenly. Use 1/4 c batter for a 10-12" skillet and 2 Tbsps for an 8" skillet. It should be a thin coating of batter. If you put in too much batter simply pour it out.
Once the crepe is set, flip it over and cook another 10 seconds. Do not brown it since it will cook more in the oven.
Transfer to a plate and cover. Continue this process and stack the crepes on the plate keeping covered. The crepes will not stick together (unless refrigerated)
Pre-heat the oven to 350°
Assemble the Tartlets
Ideally the crepes (or tortillas) should be cut to 2½″-3" circles. Use a biscuit cutter or the mouth of a glass. If using tortillas, heat them in the microwave for 7-8 seconds to make them a bit more pliable and cut out just like the crepes.
Spray the muffin tins with canola or baking spray. Reheat the cut circles in the microwave for a few seconds if they have cooled. Cover the warmed circles with a towel while you work.
Take one circle and push it into a well of the muffin tin. No need to worry if it cracks a little bit.
Spoon in about 1 tablespoon of the filling mixture.
Bake the tartlets
Bake for 10-12 minutes or until the edges of the tart shell start to brown. Serve immediately.