Remove the butter from the refrigerator in advance. Prepare a pastry bag and baking paper. Preheat the oven to 180°C and prepare the mixer.
Prepare the dough: pour milk and water into a saucepan or saucepan, add butter, salt and sugar.
Stirring, heat the mixture until the butter has dissolved, but do not bring to a boil. Reduce heat to low, add flour and stir vigorously with a spatula for 3 minutes. Then remove the dough from the heat and let cool slightly.
Beat in the eggs one at a time and mix well after adding each one. The number of eggs may vary depending on their size. Add 3 eggs and evaluate the dough: it should be smooth, shiny and slightly runny. If it is still very firm, add a fourth egg.
Transfer the dough into a piping bag. Line a baking tray with baking paper and press out eclairs 8-9 cm long, keeping a distance between them. Place in a preheated oven for 30 minutes.
Prepare the cream: using a mixer, mix condensed milk and curd cheese, then place the cream in a pastry bag.
Cool the eclairs. Make two small holes at the bottom of each and fill the eclairs with cream through them.