Melt vegan butter in a small saucepan over low heat.
Add: cocoa powder, agar agar, xanthan gum and salt, mix well.
Add almond milk, coconut milk, and maple syrup, increase to medium-high heat, and cook, while stirring, until boiling.
Add the chocolate - continue to cook while stirring until the chocolate melts.
Remove from the heat and cool for about 10 minutes. Stir occasionally with a whisk to speed up the cooling - do not cool too long, so the mixture will not set.
Add the rest of the ingredients: Espresso, almond extract, and dark rum. Mix well. Add the ground Amaretti cookies and mix well.
Transfer to individual molds or a loaf pan. Cool to room temperature. Place in the fridge and refrigerate overnight until the Bonet sets.