I assume, this is what you are looking for...
Chocolate Fondant
8 squares (250 g) dark chocolate
1/2 cup (125 ml) Sealtest unsalted butter
4 tbsp (55 ml) sugar
4 eggs (separate whites from yolks)
Preparation
1.Beat egg yolks with sugar until white.
2.Melt chocolate together with the butter.
3.When warm, but not piping hot, add melted chocolate-butter mix to egg yolks.
4.Whisk up egg whites and gently fold into the chocolate and egg yolk mix.
5.Pour batter into a 16 cm x 10 cm (6 X 4) rectangular pan lined with plastic wrap.
6.Refrigerate at least 2 hours.
I'm not sure what type of fondant mouse you're looking for. If you check my photos and look at the Cinderella cake, there's a fondant mouse on there. However, I got to design idea from another CC member, and I think her mouse looks a lot better than mine, so let me know if that's the type of mouse you're looking for and I'll try to find her picture.
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