Last time I made Tiramisu I have found that while mixing sugar and the mascarpone cheese, the mix turns liquid.When i continue with the rest of the recipe, it takes more than 1 day for it to mildly set. Please help, haven't made tiramisu in a year and would like to make it soon.
Usually tiramisu cream is a mixture of mascarpone cheese, eggs and sugar. generally you would beat the egg yolks with sugar until they are thick and moussey and then mix this into the mascarpone. This should not cause the mascarpone to be runny as mascapone has a very low water content. If you have used a low fat variation of mascarpine then this will have a higher water content and could be the cause of the problem. The other main reasons the mixture would be runny is if other liquid ingredients have been added first, or if the mascarpone has been beaten so much that it has curdled (then you will get water separating out from the cheese curds).
We would suggest trying Nigella's Tiramisini recipe (from Nigellissima and on the Nigella website), but be sure to use full-fat mascarpone. The mascarpone has only 2 tablespoons honey and 2 tablespoons Marsala added to it and then whisked egg whites are folded in. Only mix the mascarpone until the honey and Marsala are just incorporated and whisk the egg whites to soft peaks so that they are not watery. If you still find the mixture runny then it will chill and set more quickly as it is divided into individual portions. And as it is served in individual glasses you do not need to spoon the tiramisu out of a large dish.