To make the crêpe better, put the milk, eggs, oil, flour, sugar and salt in a blender and pulse until well-blended and smooth (scrape down the sides once or twice) and let sit for 20-30 minutes. It should have the consistency of heavy cream.
To make the filling, stir together the farmers' cheese, sour cream, egg, sugar and vanilla. To make the sauce, bring the cherries, sugar and water to a simmer in a medium saucepan; cook until the cherries collapse. If you'd like it thicker, stir the cornstarch into a tablespoon of cold water; add to the cherry mixture and bring to a boil. Cook for 4-5 minutes, then remove from the heat and set aside to cool.
To make the crêpes, set a medium skillet (I like my well-seasoned cast iron skillet) over medium-high heat and drizzle with oil or spray with nonstick spray. Consider the first a practice; pour a few tablespoons' worth of batter into the pan and quickly swirl it to coat the bottom - or make an even circle. Cook until the edge starts to curl from the pan and it's golden on the bottom - at this point it will be easy to slide a thin heatproof spatula under the edge and flip the crêpe. Cook for another minute, until golden on the other side. Repeat with the remaining batter. (The crêpes can be made a day ahead; keep covered with plastic.
Filling a blintz is like filling a burrito: place a crêpe on your work surface and put about 1/4 cup filling in a strip down the middle, leaving about an inch at each end. Fold one long side over to enclose the filling; fold each short end over, then flip the whole thing over to close. Fill all the crêpes and set aside (or refrigerate for up to a day).
When you're ready to cook your blintzes, heat a good-sized pat of butter in your skillet set over medium-high heat. Cook a few at a time, without crowding the pan, until browned and crisp on both sides. Serve warm, with cherry compote on top.