Toast the bread slices, use the toaster or the oven grill and then set aside.
In a medium bowl, mash half the beans with a fork and leave half whole. Add oil, garlic, lemon zest, lemon juice, oregano, salt and pepper and toss it altogether.
Assemble: place a layer of spinach leaves onto each piece of bread and top with large spoonfuls of bean bruschetta mix. Garnish with chilli flakes (if using) and enjoy!