Heat oven to 160C/140C fan/gas 3,
butter a 20cm square cake tin and line
the base with baking parchment. Pour in
half the syrup, swirling to coat the bottom.
Halve the 3 ripe bananas lengthways and
lay, cut-side down, in the tin.
Beat together the butter, sugar, eggs,
vanilla paste and over-ripe banana with
an electric whisk. Fold in the flour,
ground almonds and bicarb of soda, then
stir in the yogurt. Carefully spoon into
the tin without dislodging the bananas.
Bake for 45 mins-1 hr until a skewer
poked in comes out with only moist
crumbs. Poke all over with the skewer,
about halfway into the cake, then pour
over the remaining maple syrup. Let it
soak in for a few mins, then carefully turn
out of the tin upside-down, drizzling the
banana-studded top with more syrup.
Slice and serve warm.