Apple Buttermilk Cake

Name: Apple Buttermilk Cake
Prep time: 20 min
Cook time: 1 h 10 min
Total time: 1 h 30 min
Cuisine: British
Ingredients: 200 g plain flour (all-purpose) (BL55); 1 tsp baking powder; 1/2 tsp fine sea salt; 1/2 tsp bicarbonate of soda / baking soda; 150 ml neutral-tasting oil (vegetable or sunflower oil); 3 medium eggs (150g total); 150 ml buttermilk (see notes); 140 g caster sugar; 1 tsp pure vanilla extract or 1/2 tsp of vanilla paste; 1 tsp ground cinnamon; 400 g apples peeled and cored (4 pieces approx.)