No, don't unless you are pressed for (RL) time. In which case you probably should move to a less grindy game and wait to play Ergi on your next vacation. Mass Processing and Mass Distillery cost one energy more than just clicking the normal recipe five times in a row, and energy is going to be your limiter to do everything on time.
Inside the town hall, clicking on the desk, you open a crafting menu with the recipes for Grand Feast and Solstice, and a few other things -you craft the hot showers for the Ralf quest there, and also Bountifut Harvest wich is absolutely necessary to complete the banquet because it triples the food production, and you are going to need a lot of food for the Grand Feast: 40 rations, 20 high quality booze, and 20 herbs. the herbs alone need 20 power to craft without Bountiful harvest, but only 7 with it.
You get Fine Cloth from a quest (I don't remember which either), but you are going to need 2 anyway, because one of jostein quests also needs one. You buy it from the first market in the old town, not the one with the stalls that sells the flowers but the artisan one. It is on the second page of items, that's why you may have not noticed it
Solstice itself only needs the Grand Feast, the Fine Craft and the Fine Cloth to be crafted, it should be no problem once you have the rest of the quest items.
