For the cake: Preheat the oven to 350 degrees F. Butter a 9-by-5-inch metal loaf pan and line the bottom and sides with a strip of parchment paper.
Add the butter, ricotta and sugar to a large bowl. Beat the mixture with a hand-held mixer on medium speed until light and fluffy, about 3 minutes. Reduce the speed to low and add the eggs, lemon zest, lemon juice and vanilla extract and beat to combine. Add the flour, baking powder and salt. Fold the ingredients together with a rubber spatula until just combined. (Do not overmix.) Pour into the prepared pan and bake until a toothpick inserted in the center comes out clean, 1 hour to 1 hour and 10 minutes. Remove to a rack to cool for 1 hour.
For the assembly: Meanwhile, combine the berries, salt and 2 tablespoons sugar in a small bowl. Toss well with a fork to combine, mashing the berries slightly with the back of the fork. Allow to sit at room temperature for 10 minutes. Whisk together the heavy cream, vanilla extract and remaining 2 tablespoons sugar in a separate bowl until soft peaks form.
Dice 6 slices of lemon loaf, then divide evenly among 6 bowls or glasses. Top each serving with some of the strawberry sauce, followed by a scoop of ice cream and a dollop of whipped cream.