In a saucepan over medium heat, cook 4 tablespoons sugar, stirring occasionally, for 3-5 minutes until it melts and turns golden brown (amber color).
Remove from heat. Carefully pour ⅛ liter of water into the caramel and stir to dissolve any browned bits.
In a separate saucepan, heat ½ liter of milk over medium-high heat until it comes to a boil.
In a cup, whisk together 30 grams sugar, 40 grams cornstarch, and 3 tablespoons milk until smooth.
Slowly pour the cornstarch mixture into the boiling milk while stirring constantly to avoid lumps. Continue stirring for 1 minute as the mixture comes back to a gentle boil. It will thicken.
Remove from heat and stir in the caramel mixture until well combined. Let cool to room temperature, about 30 minutes (or refrigerate for faster cooling).
In a clean bowl, whip 1 cup cream using an electric mixer or whisk for 2-3 minutes until stiff peaks form.
Gently fold the whipped cream into the cooled caramel mixture using a spatula until no white streaks remain.
Divide the caramel cream among serving glasses and garnish with additional whipped cream if desired.