In a deep bowl, mix the mixture for dots: egg, sugar, flour, butter and red food coloring. Put the mixture in a cooking syringe and apply dots in a paper-lined pan. Place the prepared dots together with the pan in the freezer to harden for about 10-15 minutes. During this time, prepare the roll mixture: whisk the eggs and sugar together well. Then add the oil, flour and salt. Pour this mixture over the half-frozen dots. Bake in a preheated oven at 180 degrees for about 10-12 minutes. Transfer the sponge cake to a baking sheet with powdered sugar. Transfer it again so that the dots are on the bottom side and roll it together with the baking paper, then leave it to cool completely. In a deep bowl, whisk the whipped cream together with the milk and the melted but cooled chocolate. Coat the cooled roll with this filling (unwrap it gently). Then apply it on the filling and the cherry jam. Fold again into a roll, but carefully so as not to break the sponge cake.