For the layer, beat the eggs and sugar until they whiten. Add the vanilla and flour and stir until you get a smooth mixture.
Pour the mixture into a form 8 3/4″ (22 cm) in diameter with removable sides, bake in a preheated 392°F (200 °C) oven until ready. In the meantime, prepare the sugar syrup by putting the ingredients for it in a pot and heating it.
Once the sugar melts, boil for about 5 min. for the syrup to thicken. For the cream, beat the confectionery cream, put it in the fridge.
Make a mixture from the flour, egg yolks, lemon zest and 2/5 cup (100 ml) milk. Put the rest of the milk and sugar on the stove. When it comes to a boil, add the mixture while stirring nonstop. Let it cool completely and then mix with the confectionery cream.
Take the cake layer out of the form and even it out with a knife if it's become bloated in the middle. Return it to the form and pour on the hot syrup - as much as it absorbs. Let it cool completely.
Next, smear the cake layer with 1/2 the cream, arrange the eclairs, pressing them lightly into the cream. Then pour on the remaining cream and smooth it out. Leave the cake for 4-5 hours in the fridge to harden.
Run a knife along the cake form's sides and remove them. Make rosettes from the cream along the edge of the cake and pour on the strawberry jam. Chop the chocolate finely and decorate the sides with it.