As mentioned previously, whenever two types of food are mixed together, that which is in the majority or which is the principal part, is considered Ikar, and one would only recite the blessing specific to that food. Nevertheless, grain-based foods, whose blessing is “Mezonot” are considered to be a staple of one’s diet and as such are generally considered Ikar, even if they are in the minority or are not the prominent part of a dish. The Shulhan Aruch (Orah Haim 204:12) says that one caveat to this rule is if the Mezonot is in the minority and does not appreciably enhance the overall dish, such as flour which is used for consistency or adhesion. One example of such a food is licorice, which contains flour that is used simply for consistency, and therefore its blessing would not be “Mezonot” but rather “Shehakol”.
A slightly different example is schnitzel, in which the Mezonot is not the majority, but to some extent enhances the taste of food. Indeed, some Poskim rule that the blessing over schnitzel is “Mezonot”. Other Poskim follow the opinions of the Meiri and the Rosh, who say that the blessing would be “Mezonot” only when the grain-based component is the prominent part of the food, and in schnitzel, the breading is more akin to a spice or condiment. Rabbi Ben Zion Abba Shaul (Or Lezion, pg. 125) makes a distinction with regards to the thickness of the breading, with thickly breaded schnitzel having the blessing of “Mezonot” and thinly breaded schnitzel being “Shehakol”. Nonetheless, the normative opinion is that the chicken is the prominent component of schnitzel and that the breading is secondary to it, and thus its blessing is “Shehakol”.
Regarding salad with croutons, a distinction is made based on the amount of croutons used. If the salad is blanketed by a layer of croutons, it would be appropriate to recite “Mezonot” (or “HaMotzi”, depending on the crouton) and this would exempt the entire salad. If the croutons are sparse, however, one would only need to recite “HaAdama”. If one is in doubt when there is a significant amount of croutons, one could be stringent and recite separate blessings on the croutons and on the vegetables, although this is not necessary strictly speaking. Similarly, if one eats yogurt with a small amount of granola the blessing would remain “Shehakol”, but if the granola is significant, “Mezonot” would be recited.
Interestingly, the son of Rabbi Itzhak ben Oualid, Rabbi Yosef ben Oualid (Samo Yosef, § 273) writes about the Moroccan candy called “Pastille” made of eggs, sugar and some flour. Although the flour is in the minority, it still enhances the taste of the candy and the blessing is therefore “Mezonot”.
Summary: The blessing over schnitzel is “Shehakol”. The blessing over salad with croutons is “HaAdama” if the croutons are sparse, and “Mezonot” if there is a thick layer of croutons. The blessing over Moroccan Pastille candies is “Mezonot”.