I've seen that the recipe involves cream and cheese, and that may be the main cause of the GI peak (pls see my recent thread on cream & coffee).
Also, as far as I know, whey protein can cause a substantial insulin peak in blood serum even though devoid of carbs. So, theoretically, that kind of recipe even though very low-carb may not be the ideal in a weight-loosing context. Use of soy protein may avoid the issue.