54:2 The rule not to recite a bracha on the secondary food only applies when one eats the main item first followed by the secondary item and if he had in mind that his bracha on the main item should also cover the secondary item. If it’s something he normally eats together, it’s the same as having intention to eat them together. This rule also applies if one eats the secondary item at the same time as the main item, but if he had to go to another room in the interim, he must recite a bracha on the lesser item as well.
54:3 If one ate the secondary item first, for example if one ate a little something before drinking so as not to drink on an empty stomach, he must say a bracha on the secondary item. Some authorities say that since the item is of lesser importance, one would recite shehakol over the secondary food regardless of what its bracha normally is. Others disagree, so it is advisable to avoid this doubtful scenario by taking a sip of the primary item first and saying a bracha on it.