Melt the butter in a small saucepan over low heat until mostly melted but not sizzling, 2–3 minutes.
Remove from the heat and immediately whisk in the cayenne pepper hot sauce until smooth and emulsified.
Return the pan to low heat and whisk in the distilled white vinegar, garlic powder, cayenne pepper, and kosher salt. Simmer gently, whisking, until glossy and the sauce lightly coats the back of a spoon, 1–2 minutes.
Use right away to sauce hot, freshly cooked wings, or keep warm over the lowest heat, whisking occasionally. If made ahead, cool, refrigerate up to 1 week, then rewarm gently and whisk to re-emulsify before using.