Polka Dot Slice
Summarise & Save this Recipe on:
Summarise & Save this Recipe on:
Whenever I’m looking for inspiration for recipes, I go straight to my collection of old recipe books. Some from Granny (although those are very much on loan!), but most from Great-Granny. Some are proper publications, some are binders filled with recipes from magazines & newspapers, but many are little DIY books, made by groups who wanted to raise some money for whatever their cause. These are undoubtedly my favourite recipe “books”.
I first came across Polka Dot Slice in one of these lovingly made books, and I instantly knew it would be a hit with my kids. Anything containing some Smarties or M&Ms is guaranteed to please two little boys! It’s why our Rainbow Cookies are always a highly requested bake-at-home.
As expected, the kids loved Polka Dot Slice! A lovely little tray bake cake, made with coconut, vanilla and chocolate rainbow drops. What’s not to love?
The texture is less “light & fluffy cake”, and more “perfect amount of bite with sweet delicious flavours”, thanks to the desiccated coconut adding an extra dimension of texture, not to mention taste.
As is often the case in recipes inspired by the ones that I find in these little old cookbooks, I’ve played around with the various elements of this sweet rainbow cake traybake to get everything just right. My favourite addition? That sprinkling of sugar on the top, which finishes it off beautifully and adds just a little crunch too.
Ingredients for Polka Dot Slice:
Margarine or Butter
My personal preference is to use margarine due to its ease of creaming with the sugar. However, butter is perfectly fine to use, too, if you wish. Just be sure your margarine or butter is softened first, to make the creaming easier.
Caster Sugar
Polka Dot Slice is a cake tray bake, so we start with a cake-like ingredient base. Caster sugar is preferable because of this. You could swap it out for golden caster sugar if you want a slightly less-sweet option or a more caramel-y flavour.
Free-range Eggs
Again, this is a cake tray bake, so the usual cake base of butter/margarine, sugar, eggs, and flour applies. It isn’t too crucial what size eggs you use in Polka Dot Slice; just be sure to use free-range when possible.
Milk
A little bit of liquid helps make this tray bake cake batter a little easier to work with, especially once you’ve added the coconut and flour. What kind of milk you use is up to you; dairy, soya, oat, coconut, almond…all should work fine in this recipe.
Vanilla Extract
I’ve specified vanilla extract as the vanilla of choice in this traybake, but if you are feeling fancy, you could swap it out for vanilla paste or a vanilla pod. Just avoid using a vanilla essence – the synthetic taste is never really comparable
Desiccated Coconut
The coconut not only adds another level of flavour to Polka Dot Slice, but it also changes the texture from a classic sponge cake to a slightly denser tray bake cake. Alongside the vanilla and the chocolate rainbow drops, the desiccated coconut becomes an underlying, complementary taste, as opposed to a full-on flavour at the forefront.
Smarties or M&Ms
Either is fine; it’s really a case of personal preference or whichever you can get hold of more easily. I usually opt for Smarties as they are easier to get hold of locally, but M&Ms do have a slightly brighter appearance.
Top Tips for Polka Dot Slice:
• The recipe specifies you use approximately 80g of Smarties or M&Ms. The reason for this is that a tube of Smarties in the UK is usually 38g, and a bag of M&Ms is 45g. I’ve tried to give an amount that will allow you to follow the recipe without having to buy unnecessary extras or leave you short. You can, of course, use more or less to suit your taste, or to what you have readily available.
Polka Dot Slice
INGREDIENTS
- 115 g Soft Margarine (or Butter) (at room temperature)
- 115 g Caster Sugar
- 2 Free-range Eggs (at room temperature; see Egg Size note below)
- 2 tbsp Milk
- ½ tsp Vanilla Extract
- 50 g Desiccated Coconut
- 140 g Self-raising Flour (see Self-raising Flour note below)
- 80 g Smarties (approx.)
INSTRUCTIONS
- Preheat your oven to 180°c (160°c for fan-assisted ovens, Gas Mark 4 or 350°F). Grease and line a 28×18cm (11×7 inch) baking tin with
greaseproof paper . Set aside. - In a large bowl, cream together the butter/margarine and sugar until light and fluffy. Mix the eggs one at a time, mixing through before adding the next. Add the milk and vanilla extract. Mix through to combine.
- Add the coconut and mix through until combined.
- Sift in the flour, then fold together to create a batter.
- Add the majority of the Smarties/M&Ms, holding back some (to top the Polka Dot Slice before baking). Mix through until evenly distributed in the batter mixture.
- Spoon the mixture into your pre-lined tray, spreading evenly to the edges. Top the cake with the remaining Smarties/M&Ms. Bake in your preheated oven for 20-30 minutes, until golden in colour and a skewer inserted into the middle comes out clean.
- Allow your Polka Dot Slice to cool for a few minutes before sprinkling a little extra sugar over the top of it, while still warm. Once completely cool, remove from the tray and cut into individual portions.
IMPORTANT NOTE:
All my recipes are developed using a digital scale and the metric system (grams and millilitres). Cup measurements are available as a conversion but these, unfortunately, won’t always be as accurate. For best results, I always recommend baking with a digital scale.
RECIPE NOTES:
Tried this recipe?
Tag @bakingwithgranny or use the hashtag #bakingwithgranny!Frequently Asked Questions:
Sure, why not? It will obviously take away the rainbow polka dot finish, but there’s no reason you can’t tailor the recipe to your personal taste. Some alternatives I think would work well could be chocolate chips, fudge chunks, chopped nuts or even dried fruits.
We love coconut and think it is a must-have in this recipe. However, a possible alternative ingredient that may work is ground almonds. I haven’t tried and tested this, but it could be worth a shot if you really don’t like coconut and still want to give this recipe a try.
Free-from & Vegan:
Nut-free: This recipe for Polka Dot Slice doesn’t contain any nuts (coconut isn’t a nut, despite the name) but be sure to double check each ingredient for any hidden allergens.
Dairy-free: To make your Polka Dot Slice dairy-free, simply use a dairy-free margarine, a dairy-free milk and Daisy & Dom D&Ds.
N.B. Any advice or suggestions to make recipes “free-from” or vegan are purely that – suggestions. Please be careful to double-check all ingredients individually, taking extra caution when serving to those with allergies & intolerances.
For more info on common food allergies, please see food.gov.uk | For more info on coeliac disease, please see coeliac.org.uk | For more info on a vegan diet, please see vegansociety.com
ABOUT THE AUTHOR
Amy Reid
Amy Reid is an award-winning food blogger, mother, wife and cookbook author. Inspired by her childhood in the kitchen with her Mum – a professional baker and her children’s Granny – Amy now shares her tried-and-tested traditional home baking recipes with bakers of all abilities around the world. She lives in Scotland with her husband, two sons and her small pack of Siberian huskies.