And there is even a guru who doesn't think the A1c is all that reliable a marker. https://chriskresser.com/why-hemogl...eliable-marker/
The blogger who has the most information about foods that raise insulin in absence of raising blood glucose is Marty Kendall, https://optimisingnutrition.com/201..._insulin_index/ but you may be getting confused by details which are secondary to eating a "well-formulated" Low Carb meal and fasting.