I always like the family coming to tea or coffee so I can try out new recipes.
One grandson can’t tolerate dairy produce and this Parsnip and Pecan Loaf cake from Waitrose magazine has vegetable oil instead of margarine or butter.
Their recipe has a topping which contains cream cheese so I substituted chopped pecans. In any case, it’s easier to freeze any that’s left over if it doesn’t have a thick fluffy topping.
You can read about how I learned to cook at a Cookery School for debutantes when I was 5 months pregnant in Chapter 19 of my memoir Woman in a White Coat
My slightly modified recipe