To play this discussion out further: it depends on the heat and it depends on the motion. I’ve made plenty of Hollandaise (which is a sibling of Mayonnaise) in

To play this discussion out further: it depends on the heat and it depends on the motion. I’ve made plenty of Hollandaise (which is a sibling of Mayonnaise) in the blender with “boiling” butter poured in, and it stays quite hot... especially when it continues to warm on the stove top. If I microwaved it from cold, it would break almost instantly.