Mix all the ingredients smoothly in a blender or food processor, or with a whisk. Refrigerate 10 minutes if you’ve used instant flour, 1/2 hour or more if all-purpose. A rest allows the flour particles to absorb the liquid, making for a tender crêpe. Heat a nonstick frying pan with bottom diameter 5 to 8 inches until drops of water dance on it; brush lightly with melted butter. Pour in 2 to 3 tablespoons of batter and tilt pan in all directions to cover bottom evenly. Cook about 1 minute, or until browned on the bottom; turn and cook briefly on the other side. Cool on a rack as you continue with the rest. When thoroughly cool, stack and refrigerate for 2 days, or freeze for several weeks.
For 8 crêpes, serving 4. Prepare 2 cups béchamel sauce (page 13); 1 1/4 cups chopped, cooked, well-seasoned spinach (page 25); 1 cup quartered sautéed mushrooms (page 31). Spread a thin layer of sauce over the bottom of a buttered gratin dish and sprinkle with 2 tablespoons grated Swiss cheese. Mix spinach and mushrooms with 1/2 cup of sauce and divide into 8. Spoon 1 portion on the lower underside of each of 8 crêpes. Roll up the crêpes and arrange, seam down, in the dish. Spoon remaining sauce over them and sprinkle on another 1/2 cup of grated cheese. Bake in the upper third of a preheated 375°F oven for 25 to 30 minutes, just until bubbling and lightly browned on top.
Mix a pint or more fresh sliced strawberries with a teaspoon or two each of sugar and kirsch, orange liqueur, or cognac, and let stand for an hour. Drain, spoon berries generously over the lower underside of a crêpe, and roll up. Arrange 2 crêpes, seam down, on each serving plate. Drizzle over a spoonful of berry juices and top with lightly whipped cream—crème Chantilly (page 101).
