This is a medicinal syrup (شراب, sharab) included as an appendix to an anonymous 13th-century Andalusian cookery book. The ingredients include borage, mint, and citron leaves, which are infused with a range of pungent aromatics (aloe, Chinese rhubarb, cassia, cinnamon and clove blossoms) tied in a pouch. It is sweetened with sugar.
It is purportedly beneficial for weak stomachs, while strengthening the liver and assisting digestion. More importantly, it also gladdens the heart, hence its name. Honestly, I didn’t notice any differences in my stomach or liver, but I can attest to the fact that drinking this syrup lifted my spirits!