Crumble together the flour, baking powder, sugar and butter. Press into the greased tin to form a base, bake a bit (about 5 minutes if your oven is truly heated.)
Meanwhile, beat the eggs, mix in the vanilla, salt, brown sugar, flour, and walnuts. Spread this filling on the base. With a teaspoon, distribute the jam in dollops over the filling.
Bake about 25 minutes or until golden brown.
Let cool. When cool, put a teaspoon of icing sugar in a strainer or sieve, and dust the squares.
You can easily use whatever kind of fruit jam you wish instead of the apricot (though the apricot is amazing with the walnuts.) You could just check the fridge to see what jar of jam needs finishing up.This recipe was popular in the 1970s in small-town Ontario, Canada.