I'm afraid I'm not familiar with the Mitford books, but here are some recipes for you:

Marmalade Cake(Scottish)


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* Exported from MasterCook *

Marmalade Cake(Scottish)

Recipe By :
Serving Size : 4 Preparation Time :0:00
Categories : Cakes

Amount Measure Ingredient -- Preparation Method
-------- ------------ --------------------------------
1 C. self rising flower
2 Eggs, beaten
6 TB. powdered sugar
1/2 C. Margarine
dash Vanilla extract
2 Tb. Orange marmalade
1 Tsp. Finely grated orange rind
2 Tb. Milk
pinch of Salt

Set oven to 350°. Grease a 6 inch round cake pan.
Sift the flour and salt into a bowl. Rub in the
margarine until the mixture resembles fine
breadcrumbs. Stir in the sugar and half the orange
rind and then add the eggs, marmalade, milk and
vanilla extract. Mix well together to the consistency
of a thick batter. Transfer to the tin and bake in the
centre of the oven for approximately 1 hour 20 minutes
until golden in colour or until a skewer inserted into
the cake comes out clean. Sprinkle the remaining orange
rind over the top. Leave in the tin for a few minutes
before turning out on to a wire rack to cool.

From the booklet Scottish Teatime Recipes




* Exported from MasterCook *

MARMALADE CAKE

Recipe By :
Serving Size : 8 Preparation Time :0:00
Categories : Cakes

Amount Measure Ingredient -- Preparation Method
-------- ------------ --------------------------------
-----S.J. CRAWSHAW-----
3/4 c Margarine
1/3 c Sugar
2 lg Eggs
6 tb Orange marmalade
2 c Self rising flour
1/2 c White raisins (Sultanas)

Cream margarine until soft and add sugar and beat
until light and fluffy. Add the eggs one at a time,
beting well between each addition. Mix in marmalade,
sultanas and flour.

Turn into greased and bottom-lined deep 7 inch cake
tin. Level the surface, and bake at 350 for 1 - 1 1/2
hours or until a skewer comes out clean. Cool for 15
minutes and turn out onto rack to cool completely.