The aims of this study were to evaluate: (i) the chemical and nutritional composition of rice before and after cooking and (ii) postprandial glycemic impacts in children and adolescents with type 1 diabetes (T1D) after eating two different types of rice (“Gigante Vercelli” white rice and “Artemide” black rice) or white rice cooked “risotto” style or boiled using an advanced hybrid closed loop (AHCL) system (Tandem Control-IQTM). General composition and spectrophotometric analyses of raw and cooked rice were performed. Eight T1D subjects (four males and four females, aged 11 ± 1.4 years), two with celiac disease (CD), using an AHCL system were enrolled. “Gigante Vercelli” white rice cooked as risotto or boiled and boiled “Artemide” rice were prepared by the same cook on two evenings. Continuous glucose monitoring metrics were evaluated for 12 h after meal consumption. Total dietary fiber was higher for both rice types after cooking compared with raw rice. Cooking as risotto increased polyphenols and antioxidants (p < 0.05) in both rice varieties, and total starch decreased after boiling (p < 0.05) in white rice. There was a significant peak in glycemia after consuming risotto and boiled white rice (p < 0.05), while the mean glycemic peak remained <180 mg/dL in individuals eating boiled Artemide rice. There were no significant differences in automatic basal or auto-bolus insulin deliveries by the AHCL according to different types of rice or cooking method. Our findings suggest that glycemic trends are impacted by the different chemical and nutritional profiles of rice but are nevertheless well controlled by AHCL systems.