In a blender or food processor, combine flour, milk, water, eggs, olive oil or melted butter, and salt. Puree or blend until smooth. Pour batter into a pitcher or container with a pouring lip (or leave in blender jar). Cover with plastic and refrigerate for at least 30 minutes, (optional).
Heat the remaining 1 tablespoon of olive oil in a large nonstick skillet over medium heat. Add leeks and saute 5 minutes, until tender. Add chorizo and cook 3 to 5 minutes, until heated through. Remove mixture from pan and set aside. Cover with foil to keep warm.
Return skillet to medium heat.
For each crepe, add 2 tablespoons batter to pan. Lift the pan off the heat and tilt and rotate it so that the batter forms an even, very thin layer. Cook until the top is set and the bottom is golden (about 30 seconds to 1 minute). Using your fingers, flip crepe and cook 30 seconds, until second side is lightly browned. Transfer crepe to layers of waxed paper and repeat with remaining batter.
Roll crepes with chorizo-leek filling. Garnish with sour cream and chives.