Wash the strawberries well and break off the stem. Sprinkle with a little lemon juice then purée them with the blender. Strain the purée and set aside.
Preheat the oven to 180° C/356° F and prepare a 12-cup muffin pan. Cream the soft butter at room temperature and the sugar. Separately mix the flour with the salt, baking soda and bicarbonate.
Add 2 tablespoons of flour to the butter cream and one egg. Mix well until smooth. Do the same with the next egg. Add the rest of the dry ingredients and the yogurt. Finally, add 2 tablespoons of strawberry purée and vanilla extract. Homogenize gently.
Distribute the mixture into the 12 cups. Place a spoonful of strawberry purée on top of each cupcake. Marble with the tip of a knife.
Put the cupcakes in the oven and bake for 25-27 minutes, until they pass the toothpick test. Place them on a rack to cool.
For the coulis
To prepare the strawberry coulis, combine fresh strawberries, sugar, and a splash of lemon juice in a saucepan. Simmer the mixture over low heat for 8-10 minutes, allowing the strawberries to break down and release their juices.
Transfer the cooked mixture to a blender and puree until smooth. For a finer texture, strain the coulis through a fine-mesh sieve to remove any solid parts.
Allow the coulis to cool to room temperature.
For the topping:
Mix the whipping cream with the powdered sugar until fluffy. Add the grated lemon zest and lemon juice and mix gently.
Decorate each cupcake with the lemon-flavored whipped cream. Top with a spoonful of cooled strawberry coulis. Decorate each cupcake with a fresh sweet strawberry. Enjoy!