Delicious cold with a cup of tea or coffee, these are a quick and easily made treat. Can also be heated and served as a pudding with custard, cream or ice cream.
Preheat the oven to 170C/ 150C Fan / Gas 3
Butter a baking tin approximately 20cm square.
For the base:
Stir the flour, salt and sugar together in a bowl.
Rub the butter into the flour mixture and bring it together into a rough ball of dough.
Press the dough evenly into the base of the baking tin, making sure you go right to the edges. Smooth, the top with the back of a spoon.
Spread the jam over the shortbread base, leaving a 1cm bare edge all around (the jam will spread as it heats up).
For the crumble topping:
Rub the butter into the flour, salt and spices if using.
Stir in the sugar, oats and chopped nuts if using.
Add 2-3 drops water and, using your hands, bring together small pieces of the topping so that it forms differently-sized pieces of crumble.
Sprinkle the crumble topping over the jam so it's completely covered.
Place in the preheated oven and bake until cooked through, browned and with the jam just starting to bubble through the topping (approx 35 min).
Remove from the oven and cut into 9 squares while still hot.
Leave in the tin until completely cold.
Remove each square with the help of a round bladed knife.
Eat cold or reheat in a microwave for 20 seconds and serve with custard, cream or ice cream.
Cold Jammy Shortbread Squares will keep in an airtight container for 3 days or can be frozen.