סימן קלה סעיף יג
מִי שֶׁהוֹלֵךְ אֲפִלּוּ בְּאֶמְצַע סְעוּדָתוֹ לְסֻכַּת חֲבֵרוֹ וְאוֹכֵל שָׁם שִׁעוּר דְחַיָב בַּסֻּכָּה, צָרִיךְ לְבָרֵךְ גַּם שָׁם לֵישֵב בַּסֻּכָה.
If you leave the sukkah even in the middle of your meal, to go to a friend's sukkah, and you eat a quantity of food which must be eaten in the sukkah, you must say Leisheiv basukkah there too.17Many later Poskim maintain that this is not considered an interruption if you had intended to go to another sukkah when you initially said the berachah, and that it is not necessary to say another berachah in the second sukkah. Beis Meir writes that you need not say another berachah even if you had no intention to eat in another sukkah. In situations where there is a doubt regarding berachos, the rule is that we are lenient and do not say the berachah. It is the best practice, therefore, not to leave the sukkah in the middle of the meal. (Ibid 639:48)
תנא דבי אליהו כל השונה הלכות בכל יום מובטח לו שהוא בן העולם הבא שנאמר הליכות עולם לו אל תקרי הליכות אלא הלכות (נדה ע"ג.)