Cream the sugar and the butter together until fluffy.
Add the eggs one by one and mix them in well with a wooden spoon.
Add the vanilla bean paste or extract.
Fold in the flour and baking powder.
Line your slow cooker pot. I use a round 3.5 litre slow cooker to make cakes, and line it with 2 large paper cake cases or loaf cake cases (available in pound shops etc). You could also use baking paper.
Spoon half of the cake mixture into the lined pot. Add four to five heaped teaspoons of marmalade on top of the cake mixture and marble it in with a knife, then spoon the rest of the cake mixture on top.
Add four to five more heaped teaspoons of marmalade on top. Use a knife to marble it through the cake mixture.
Put the lid on the slow cooker with a tea towel tucked under it to catch drips. Make sure you fold up the sides of the tea towel over the lid of the slow cooker, so they don’t hang down over the edges of the crockpot.
Bake on high for about 1.5-2 hours or until a knife comes out clean from the centre of the cake. The time really varies depending on your slow cooker so keep an eye on it! If the sides start to burn, rotate the bowl within the slow cooker or turn it to low.
When ready, let it cool a little then use the edge of the cake case to pull the cake out of the pot, and leave it to cool fully on a rack.
Make the glaze by warming 3-4 tablespoons of marmalade gently in the microwave in a small bowl.
When the cake is cold, pour the marmalade over it and spread to the edges.
Serve and enjoy!