Layered banana butterscotch cake

Ingredients

• 375 gram butter, at room temperature
• 6 eggs, at room temperature
• 2 cup (440g) caster sugar
• 2 cup mashed overripe bananas
• 3 cup (450g) self-raising flour
• 1/2 cup (75g) plain flour
• 2 cup (240g) pecan halves
• Butterscotch frosting
• 1 cup (220g) firmly packed light brown sugar
• 1/2 cup (125ml) pouring cream
• 125 gram butter, at room temperature
• 250 gram cream cheese, at room temperature
• Butterscotch sauce
• 185 gram butter, at room temperature
• 1 cup (250ml) pouring cream