Step 1: Preheat your oven to 400°F (200°C) and line two baking sheets with parchment paper for the salted caramel profiteroles recipe.
Step 2: In a medium saucepan, combine the water, 1/2 cup butter, and 1/4 tsp salt. Bring to a rolling boil over medium-high heat.
Step 3: Reduce heat to low and add the flour all at once. Stir vigorously with a wooden spoon until a dough forms and pulls away from the sides of the pan.
Step 4: Continue to cook the dough for 2 minutes to cook out the flour taste, then remove from heat and let cool for 5 minutes.
Step 5: Add eggs one at a time, beating thoroughly after each addition until the dough is smooth and glossy with a V-drop consistency.
Step 6: Pipe 1-inch mounds of dough onto the baking sheets and bake for 20-25 minutes until golden brown and firm.
Step 7: Remove from oven, poke a small hole in the side of each bun to release steam, and let them cool completely on a wire rack.
Step 8: To make the caramel, melt the granulated sugar in a heavy saucepan over medium heat, stirring constantly until it turns a deep amber color.
Step 9: Carefully whisk in 6 tbsp butter and 1/2 cup heavy cream (it will bubble!). Stir in the sea salt flakes and let cool slightly.
Step 10: Whip the 1.5 cups heavy cream with powdered sugar and vanilla until stiff peaks form. Pipe into the cooled buns and dip the tops into the salted caramel sauce.