Pour the cream into a small saucepan with a lid, scrape the seeds from the vanilla bean into the pan, then add
the vanilla bean pod and heat over medium heat until steamy, swirling the pan occasionally. Remove from the heat, cover, and let steep.

Pour 1⁄4 cup water into a heavy- bottomed saucepan. Add the corn syrup, then carefully pour the sugar into the center of the pan. If any sugar crystals stick to the sides of the pan, brush them down into the water with moistened fingers. Cover and cook, without stirring, over medium heat until the sugar is dissolved, about 3 minutes. Uncover and continue to gently boil, without stirring, until the mixture turns a deep amber, gently tilting the pan to encourage even caramelization. This will take only a few minutes; watch the pan carefully toward the end and reduce the heat to low if needed.

When the mixture turns a dark
amber, remove the pan from the
heat, immediately swirl in the butter, then gently and slowly whisk in the cream mixture. Return the pan to low heat and whisk gently to dissolve
any hardened caramel. Strain into a heatproof bowl and let stand, stirring occasionally, until cooled. Stir in
1⁄2 teaspoon flaky salt, crushing any extra-large bits between your fingers, and season to taste with more salt.