Crush the digestive biscuits into fine crumbs using a food processor or rolling pin. Melt butter and combine with biscuit crumbs. Press into the bottom of a springform tin. Chill for 30 minutes.

Melt butter and brown sugar in a saucepan over low heat. Stir until dissolved, then add condensed milk and bring to a gentle boil for 5 minutes until thickened. Cool slightly.

Pour warm toffee over chilled biscuit base, smooth out, and refrigerate for at least 4 hours until firm.

Slice bananas and arrange over the toffee. Maintain balance with sweet toffee beneath.

Whip cream with icing sugar and vanilla until soft peaks form. Spoon over bananas.

Crumble chocolate on top and keep refrigerated until serving.