Preheat the oven to 375 degrees.

Line the loaf pan with parchment paper, that comes all the way up the sides. Some folds are fine and add to the rustic loaf and crunchy sides.

In a food processor combine flour and whole almonds. Process until finely ground (the flour will allow you to process the almonds without them becoming a paste).

Add the baking powder and salt and briefly mix again.

In a large bowl whisk the oil, granulated sugar and lemon/orange zest.

Whisk in egg.

Whisk in almond extract and half and half (milk/cream).

Add in the flour combination and whisk altogether until combined.

Pour into the parchment lined long loaf pan.

Place the halved plums cut side up in a straight line along the top of the batter, being careful to not touch the plums to the sides (or they will burn).

In a small bowl combine the room temperature butter and sugar. Then add in the sliced almonds, combine with your fingers and sprinkle in even clumps over the top of plums and batter.

Bake for 45 - 60 minutes (depending on the oven) until a toothpick comes out of the batter (not a piece of fruit) clean and the top is nicely brown and crisped.

After allowing to cool for 5 minutes, use the overhang of parchment to carefully lift the cake onto a cooling rack. Gently peel back the parchment paper sides and allow to cool.

Serve warm or at room temperature.