21. Fried Matzah:

If the Matzah is a Kezayis in size when fried:[1] Then irrelevant of the amount of oil used, even if the Matzah is deep fried, it remains Hamotzi.

If the Matzah is less than a Kezayis in size prior to frying: If the Matzah was less than a Kezayis in size from the start of the frying, then if a very minute amount of oil is used for the frying simply so the dough does not stick, the Matzah remains Hamotzi according to all.[2] If however one uses a larger amount of oil then it is disputed[3] as to its blessing, and the main ruling follows that it should only be eaten within a meal, and if one does not do so then he should recite Mezonos and Al Hamichyah. Thus, in order to avoid turning the Matzah into Mezonos, one should use a minute amount of oil if the Matzah pieces are less then a Kezayis.

If the Matzah’s started off a Kezayis and through the frying became less than a Kezayis in size:[4] The Matzah is Mezonos unless a very small amount of oil was used simply so the Matzah does not stick, in which case it remains Hamotzi. In the event that a nice amount of oil was used, but it was not deep-fried, then one is to be stringent not to eat such bread to the point of satiation unless it is eaten within a meal.

[1] Seder 2:12

[2] Seder 2:11

[3] See Seder 2:12-13 that there are two disputes in this matter, one regarding if frying is considered like cooking or baking [Seder 2:12], and another in whether cooking less than Kezayis bread pieces makes it become Mezonos [Seder 2:13].

[4] See Seder 2:12-13