Cut the butter into small pieces, soften it and add fine sugar.

Beat with an egg beater until the color becomes lighter and the volume becomes larger.

Add the whole egg mixture twice and beat well.

Sift in low-gluten flour and baking powder, and stir into dough.

Brush a thin layer of baking pan oil on the bottom and four walls of the 8-inch square movable bottom die.

Spread the dough flat in a square mold, flatten it with a rubber scraper or gloves, and then flatten it by hand.

Put it in the middle layer of the oven preheated to 175 degrees, bake for 20 minutes until the surface is golden, and then take it out.

After the bottom of the biscuit is cooled, make toffee nut filling. First, break the walnuts a little.

Put all the brown sugar, golden syrup, butter and lemon juice into the milk pot, and heat it on low heat, stirring it while heating to prevent it from sticking to the bottom.

After heating to boiling, continue heating for about 3 minutes until the butter and brown sugar are completely mixed together and produce a lot of foam.

Turn off the heat, pour in walnuts and mix well.

Pour walnuts into the bottom of the biscuit while it is hot and flatten it. Then, put the mold back into the oven, bake it at the original temperature for 8~ 10 minutes, then take it out, cool it, cut it into pieces and seal it.