It is an underrated (British) classic, but I don’t like jelly in it myself.
The syrup here consists of strawberry juice, sugar and Framboise liquer that’s been reduced down to high viscosity. The Framboise really adds a fantastic dimension.
This one has alternating layers of fresh strawberries, lightly poached strawberries in syrup, (real) vanilla icecream (of course), syrup and crème anglaise. A great summer treat.