Chill your glass. Pop your serving glasses in the freezer for 5–10 minutes. Cold glass = slower melt and better presentation.
Whip the cream. In a cold bowl, whip the heavy cream with powdered sugar until soft peaks form. Don’t overdo it—soft and glossy is perfect. Transfer to a piping bag or zip-top bag with the corner snipped.
Blend the base. Add strawberry ice cream, 1/2 cup milk, fresh strawberries, jam, vanilla, and a pinch of salt to a blender. Blend until smooth. If it’s too thick to move, add a splash more milk.
Taste and tweak. Need more sweetness? Add a bit more jam. Want it brighter? A few drops of lemon juice. Prefer it thicker? Toss in a handful of frozen strawberries or another scoop of ice cream.
Swirl setup. Pipe a ring of whipped cream along the inside of the cold glass, spiraling it from top to bottom. This gives you the signature swirl as the shake pours in.
Pour and swirl. Gently pour the milkshake into the glass; rotate the glass slightly to encourage the swirl pattern. Top with a generous cloud of whipped cream.
Finish strong. Garnish with a halved strawberry, a drizzle of strawberry jam, or crushed freeze-dried strawberries. Add a wide straw for maximum sip-per-second efficiency.
Serve immediately. This is not a “let it sit” situation. Cold, creamy, and gone—like it should be.