A mighty moist cake with marzipan and ginger with a gooey rhubarb topping concocted from the by-product of making rhubarb syrup for rhubarb cocktails. Basically I had cooked up a heap of rhubarb, then I drained it overnight resulting in a cerise pink syrup for said cocktails and was left with a large quantity of rhubarb pulp.
I had a birthday lunch last Saturday and I needed a good dessert to serve about 20 of us, so I used the rhubarb pulp to make this cake using double quantity of my Blueberry Frangipan Cake recipe. This makes a big old cake, but you could of course halve the recipe and cook in a 25 cm tin.
Rhubarb and Almond Upside Down Cake
Serves at least 20
For the cake
2250 kg raw rhubarb, trimmed, (gives you about 2 kg of trimmed weight) plus about 6 extra stalks
1 kg granulated sugar
54o g caster sugar plus 1 teaspoon vanilla extract or just use vanilla sugar, see note below
500 g unsalted butter, softened
8 medium eggs
500 g ground almonds
400 g self-raising flour
150 g marzipan, broken into little chunks
50 g crystallised ginger, optional
For the topping
1700 g rhubarb, trimmed (gives you about 1500 g trimmed weight)
750 g white sugar
2 large oranges
Custard or Greek Yoghurt to serve.
1. For the cake, cut the 2 kg of trimmed rhubarb for the cake into 4 cm pieces and drop them into a large pan.
2. In goes the granulated sugar, then cover the pan with a lid and slowly bring it to a boil. Stir it a couple of times and cook the rhubarb until it gradually becomes tender and collapses. Whip it off the heat and leave it to cool.
3. Line a large sieve with a piece of muslin, (an old clean (!) t-shirt rag would do the trick, or just a fine sieve, if that’s what you’ve got.) and tip all the cooked rhubarb into it. Leave it to sit overnight to gently drip through. You should now have 1 litre of rhubarb syrup and 1500 g pulp. (Use the syrup here to make Rhubarb cocktails.)
4. Separately cook the rhubarb for the topping with orange. Cut the remaining 1500 g of trimmed rhubarb as above and tip it into a pan and finely grate in the zest of one of the oranges and squeeze in the zest of the two and once again, cover and cook until tender. Once cool, drain this overnight as above too. Reserve the resulting rhubarb and orange syrup aside to use for topping. (Use the pulp from this batch of rhubarb to make ice lollies. (recipe coming.)
5. Preheat the oven 170°C/ gas 3 and grease and line the base and sides of a 30 cm cake tin. Weigh out all your cake ingredients and then crumble the marzipan into pieces a bit bigger than the size of a pea and then chop the ginger into similar size pieces.
6. You will need a large mixer to deal with this amount of mixture. (I use a vintage Kenwood chef) Beat the eggs lightly with the vanilla, if using. (see ingredients list above) Whiz the the sugar and butter until pale, light and fluffy, then mix in the flour, salt, ground almonds and the eggs until smooth.
7. Turn mix into a bowl, then toss in the marzipan and ginger, (if using) and stir well, then fold in half of the rhubarb pulp and mix well again.
8. Cut the extra 6 sticks of rhubarb and lay in the bottom of the lined cake tin Spread the remaining rhubarb pulp evenly over the raw rhubarb sticks and base of the tin. Then spread the cake mix over the top.
9. Place in the middle of the oven and bake for about 2 hours (check how it is every 1/2 hour) until golden and a skewer comes out almost clean when inserted into the centre.
Let cool for 10 minutes in tin on a wire rack, then invert onto a large plate/platter.
10. Pour the reserved rhubarb and orange syrup into a pan, bring to a boil, reduce heat and simmer until reduced by half, then use this to paint onto the rhubarb surface of the cake which gives it a glorious gloss.
Yum yum yum.
Little note….I keep a separate jar of caster sugar into which I bury any used vanilla pods I have left over form a recipe. Just wash and dry them and they will impart loads of lovely vanilla flavour into your sugar. Commercial vanilla sugar I find tends to be too strong.