For the base: crumble biscuits in a food processor finely and add butter. Line springform pan with a mixture and make 1 cm (approximately 1/2 inch) high edge all around.
For the topping: rinse lime in hot water. Grate zest of 1/2 lime. Finely peel the other half and set aside peel for garnishing.
Squeeze all lime juice and combine with zest. Whisk egg yolks with a whole egg, condensed milk and lime juice until smooth. Spread mixture over pastry base.
Bake in preheated oven at 180°C (approximately 350°F) for about 30 minutes. Cover with aluminum foil if tart browns too quickly.
Remove from oven, cool and garnish with lime peel. Serve.