NOTE 1. I always suggest using kitchen scale to get accurate weight.
NOTE 2. Petit buerre cookies and graham crackers might not weight the same, so use as many as you need to line 3 layers
NOTE 3. You can add more or less sugar, depending on your taste, but keep in mind that cream is already sweetened by white chocolate and that we are using jam (which is sweet by itself)
NOTE 4. Per layer add as many jam as you need to generously cover the cookies/crackers