Step 1

Add whey to a heavy stockpot on low/medium heat and simmer down at least 1/2 over the course of an hour. (Low and slow is better than risking it by scorching the pan on too high of a temp).

Step 2

Once reduced, add the sugar, vanilla bean seeds, butter, and lemon juice (if using sweet whey). Stir occasionally on low/medium until well combined, then slowly raise the heat to medium.

Step 3

Stir frequently, as over the next 30-45 minutes the whey will slowly start to caramelize and reduce to a syrupy consistency. Be patient because it can scorch if left unattended.

Step 4

The whey will slowly change colors and become more brown, then start to foam - continue to stir more often as it caramelizes incredibly quickly. Once it thickens to the point that it coats the back of a spoon, remove from the heat and stir as it cools.

Step 5

The whey caramel will thicken considerably as it cools.