Baking – How to make liquid glucose from powdered glucose

First of all- glucose is a different sugar than table sugar. Corn syrup in the US is similar but has a few extra compounds. As far as I can tell it is used for similar reasons as liquid glucose in the EU. http://www.ochef.com/784.htm

It is used for a couple reasons:

1. it is thicker than sugar syrups.
2. when making candy a little corn syrup can be added to the sugar solution to prevent crystallization.
3. in the US at least, it is much cheaper than cane sugar.

You can buy it in stores here- I can't say whether you can in Belgium.

I have, on occasion, been forced to use a very thick sugar syrup in place of corn syrup. The recipe used the syrup for reason #1 above and turned out well. If it had been in there for reason #2 it would have been less successful.

In general, if you can find it, it is probably better to buy than to make a substitute because of reason #3.

A simple alternative would be to make a ganache flavored with Frangelico or another hazelnut liqueur. This has the advantage of having much less sugar, and probably better overall flavor, than an even-more-sweetened Nutella, assuming you start with a reasonably dark chocolate. All you do is boil cream, and pour it over a similar quantity by weight of chopped chocolate, into which you've added a healthy splash of hazelnut liqueur (or the liqueur can go into the cream as you bring it to a boil; either way works in my experience). Then stir vigorously until all the chocolate is smoothed out. You can pour it over while the mixture is still moderately warm and refrigerate it with the cheesecake. It will not be Nutella, but from experience it will be good, and evoke the same basic flavors.

Alternatively, most cheesecakes I am familiar with aren't topped with an icing, but a mixture of say cream or sour cream and other ingredients, sometimes added in the last few minutes of baking. These usually spread out reasonably well. You could consider softening the nutella in the microwave and mixing with a bit of cream, which will be a sort of less heavy ganache.