A fully cooked nut paste will have a noticeably deeper color, a fragrant aroma, and will pull away cleanly from the sides of the pan. It should also have a smooth, slightly glossy appearance.
Determining when a nut paste is fully cooked involves observing several key indicators. Here's a step-by-step breakdown:
Color Change: As the nut paste cooks, it will transition to a richer, deeper shade of brown. This is a primary visual cue that the sugars are caramelizing and the nuts are roasting properly.
Aroma: A distinct, fragrant aroma will develop as the nut paste cooks. This indicates that the volatile compounds responsible for the nutty flavor are being released. The aroma should be strong and appealing, not burnt or acrid.
Consistency: The nut paste will thicken as it cooks and the moisture evaporates. When stirring, it should pull away cleanly from the sides and bottom of the pan, leaving a temporary trail. It should also have a smooth, almost glossy appearance.
Taste Test (Optional and Careful): If you're comfortable, you can carefully taste a small amount of the nut paste. It should have a rich, nutty flavor with no raw or gritty texture. Be extremely cautious as the paste will be very hot.
Use a heavy-bottomed pan and stir the nut paste constantly over medium-low heat to prevent scorching. Burnt nut paste will have a bitter taste and ruin the entire batch.