Sometimes I make order cakes for family/friends/friends' friends and this was one of them - the girls surname is Chmura which means 'cloud' in Polish, so the order was to make a blue cake with fluffy clouds, plain flavored, with some fruit. They liked the cake and it was easy and pleasant to make, so everyone was satisfied. It's a very simple decoration but it looks really love in real, so it should work for any kids' parties you might have upcoming in the future :)
cloudy sky birthday cake
sponge cake
(for 1 round 22cm / 9” cake, to be cut in 3 layers)
4 eggs, separated
1 cup flour
2/3 cup sugar
1 tbsp baking powder
salt
whip the egg whites with salt until foamy, then continue adding sugar in 3-4 portions and beat until stiff
beat egg yolks with mixer (in small bowl would do) until pale and fluffy
mix the two on low speed
add flour sieved with baking powder and mix delicately with rubber spatula until there are no more flour lumps
bake for 35-40 min in 180°C (i don’t preheat my oven when I bake sponge cakes, it helps the top to be more flat as the sides seem to raise more easily)
vanilla swiss meringue buttercream (i used a portion made of 6 egg whites) + blue food coloring
raspberries
assembly:
mix food coloring into 2/5 of the buttercream
place one sponge cake layer on a cake stand, top with 1/5 of the white buttercream and spread it evenly, put some raspberries onto the buttercream, repeat
make a crumb coat with the blue buttercream, let it sit in a fridge for at least half an hour, until the buttecream is firm to touch
over the cake with the rest of the blue buttercream, smooth out the top & sides
pipe clouds with the remaining white butercream (I piped half-spheres with wilton tip #2 and then created a nice cloud surface with the back of a tiny dessert spoon, you don't want the clouds to perfectly smooth though)
keep in fridge until 20-30 minutes before serving