Line a square springform pan (approx. 24 x 24 cm) with baking paper. Clean, wash, halve and stone the cherries. Coarsely chop the almonds.
Cut butter into cubes and put them in a pot with the sugar. Heat and melt butter in it while stirring. Carefully mix syrup, oat flakes, flour, almonds and cherries with the butter-sugar mixture in the pot.
Remove the pot from the heat, fill the mixture into the mould and smooth it down.
Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) for approx. 15 minutes, remove from oven and let cool on a cake rack. Carefully remove from the baking tin with the baking paper and chill for at least 4 hours, preferably overnight.
Cut into pieces of about 6 x 6 cm.