Since starch is the major energy source of the human diet, retarding starch digestion could serve as an effective way for modulating glycemic response and for the prevention and treatment of obesity. In this study, a dietary bioactive compound, ascorbyl palmitate (AP), was evaluated as a potential inhibitor in the digestion of raw, cooked, and retrograded high amylose maize starch (HAMS) and potato starch (PS). The inhibitory effect of AP was compared with that of palmitic acid (PA), without the ascorbyl group. In addition, HAMS inclusion complexes with AP and PA were formed and treated by annealing (ANN), acid hydrolysis (ACH), and the combination of both. Upon the addition of AP, the resistant starch (RS) contents in raw, cooked, and retrograded starches were increased significantly, indicating the inhibitory effect of AP against starch digestion. Although both HAMS-AP and HAMS-PA inclusion complexes exhibited minimal RS contents, all the hydrothermal treatments enhanced the RS contents in both inclusion complexes, marking their potential to serve as a new type of RS, i.e., RS5. Among the treatments, ANN followed by ACH (ANN-ACH) was most effective to retard starch digestion by increasing RS contents. The study findings could have practical implications in designing functional starch-based ingredients and increasing their nutritional value.