Greasing a cake tin is usually done to prevent the baked cake from sticking to the pan and becoming difficult or even impossible to remove without damage. While this is often enough to prevent sticking, some recipes may advise lining the cake tin with greaseproof paper or parchment paper. These papers do not break down when exposed to grease or other moisture and they create a barrier between the cake and the pan to help you easily slide the baked good out in one piece.
Trace the bottom of the square cake tin onto a piece of greaseproof paper with a pencil.
Cut out the greaseproof paper square with scissors and place it inside the cake tin. Trim the square as necessary so that it lies flat on the bottom of the tin.
Remove the greaseproof paper from the square cake tin.
Cut four 4 to 5 cm (1.5-inch to 2-inch) wide strips from the greaseproof paper, each slightly longer than the sides of the pan.
Place the strips of greaseproof paper inside the cake tin along the sides. Bend the ends of each strip so that it curves around the corner of the pan. This makes the paper lining overlap so that the cake will not stick to the corners of your cake tin.
Remove the greaseproof paper strips from the cake tin.
Brush a thin layer of melted butter or shortening onto the bottom and sides of the cake tin. This will hold the greaseproof paper lining in place.
Place the greaseproof paper square in the bottom of the cake tin and arrange the strips along the sides as you did previously. Press the paper gently against the cake tin so that it adheres to the melted butter.
Grease the greaseproof paper with additional melted butter or shortening to prevent the cake from sticking to the paper.
If your recipe advises you to grease and flour the cake tin, gently shake 7 to 15 gr (1 to 2 tbsp) of flour over the greased greaseproof paper before adding the cake batter.