For frying the blintz crepes and the finished filled blintzes, about 1/3 cup canola oil or clarified butter, or a combination of both
Mix the blintz filling ingredient in a medium bowl to have at the ready. In separate bowl, beat the wet and dry ingredients by hand until smooth and lump-free.
Lay out two or three tea towels on a counter or table surface.
Lightly brush a non-stick 7-8" skillet with a bit of clarified butter or oil and heat on medium until a drop of water sizzles.
Fill a 1/4 cup measuring cup with 3 tablespoons of batter and pour quickly into the heated pan, swirling the pan so the batter evenly coats it. The blintz will take just about a minute to be done. It's done when the center is dry to the touch. Flip it over onto one of the tea towels and repeat the process until you have all 18-20 blintz crepes laid out to cool. They will cool quickly.
Fill them by placing a heaping tablespoon of filling about 1-inch up from the bottom, folding up the bottom, folding in the sides, and rolling it up from the bottom. Place the filled blintzes seam side down on a platter and keep refrigerated until ready to fry them. I find that allowing them to chill for at least an hour or overnight helps keep them sealed nicely.
When ready to cook, fry the filled blintzes over medium-low heat in a large non-stick skillet with about 1/3 cup of the clarified butter or canola oil. Turn them once or twice with tongs, careful not to pierce the outside, until they're nicely golden brown and crispy on both sides. Remove to a platter lined with paper towels to drain, and, if necessary, keep them warm in the oven until ready to serve. A dollop of sour cream is all they need for serving.