the Prophet was asked about a mouse that fell into the cooking fat. He said: "If it (the fat) is solid, then throw it away, and whatever is around it. If it is liquid then do not use it at all."(Daif) (Using translation from Nasāʾī 4260)
سُئِلَ النَّبِيُّ ﷺ عَنِ الْفَأْرَةِ تَقَعُ فِي السَّمْنِ فَقَالَ إِنْ كَانَ جَامِدًا فَأَلْقُوهَا وَمَا حَوْلَهَا وَإِنْ كَانَ مَائِعًا فَلَا تَقْرَبُوهُ