The recipe is this (translated by me):
2 cups of all purpose flour
1 Pack. baking soda
1 lemon (zest and juice)
1 cup soy (or other vegan, I used almond) milk
1/2 cup oil
1/2 teaspoon vanilla extract
1/3 cup granulated sugar
1 cup icing sugar
Mix flour with baking soda and lemon zest. In another bowl, mix oil, milk and granulated sugar with half of the lemon juice. Combine both mixes and mix quick, but careful (no more lumps of flour but don't over mix, otherwise the batter will be too wet). Bake in a fatted from for 45 min at 180 °C.
Prepare frosting by mixing icing sugar and half of the lemon juice. After baking, take the cake out of the form and pour frosting over it before it cools down.