Easter Monday is a holy day in Italy since the second postwar, so that workers could rest a day more after Easter Sunday.
According to tradition, this day should be celebrated outdoor with family or friends, by plannyng a trip into the country just outside town, or, weather permitting, to the seaside, to have picnic or barbecue.
Of course, that being the case, you can bring any leftovers from the previous day. Here in Campania a classic food for outdoor trips is casatiello (or tortano: the difference is that in the first one you put raw eggs, with their shell intact, on the surface, held by stripes of dough; in the second eggs are hard-boiled, shelled, cut and put inside the dough). Many people also love bringing pasta frittata.
If nothing is left from the previous day, you need to make some savory pies, like torta pasqualina (Easter cake), or similar, to accompany barbecue.
Of course, you should also bring something sweet, like cookies or pastiera, and, of course, chocolate from your eggs, and maybe some colomba.