Start by adding into a large bowl the strawberries and the biscuits previously broken into small pieces and, with a spatula, mix it all together very well.
Then add 3 tablespoons of icing sugar and the yogurt, with the spatula, mix it all together very well again, until a smooth mixture is formed.
Set aside.
Grease a baking dish with butter, transfer all the mixture we've just made to it and spread very well, leaving it as flat as possible.
Cover the baking dish with plastic wrap.
Take it to the fridge and let it chill for 2 hours.
When it's almost time to take it out of the fridge, add the whipped cream mixture and 1 tablespoon of icing sugar into a bowl, beat very well with a mixer until stiff peaks are formed.
After the indicated time, take the dessert out of the fridge, unwrap it, and spread all the whipped cream over the dessert.
Take it to the fridge again and let it chill for another 2 hours.
Garnish with strawberries, to taste.
Serve.