Thanks winpoj for your help.
Actually I'm not sure if it is correct to call it dort, it's a tiramisu.
I have goggled it and have found it named dort as well as koláč.
You're right, it wouldn't be necessary to instruct the people to eat the cake after extracting it from the packaging, but some producers prefer to explain it.
For me, tiramisu is zákusek or dezert. Use Google images to see what most of the Czechs imagine under the terms dort and koláč. I suppose it is a label on the packaging, if so, the most natural option is not to name the product at all.
And mind the Czech verbs vybalit and rozbalit, the periphrasis vyjmout z obalu sounds very formal.
Also, for enjoying food and drinks we prefer different verbs, e.g. vychutnat si. Uží(va)t si is used rather for enjoying activities or for having good time.
If it is really some advertisement on the packaging, I would prefer something along this line: