Preheat the oven to 180°C.
Line a baking tray with parchment paper.
Mix 2 tbsp oil, salt and turmeric powder in a big bowl.
First you need to peel the plantains. Trim the ends first.
Cut a slit through the skin lengthwise. Using your fingers, peel away the skin.
If it is difficult to peel then use a knife to remove the peel.
Cut the plantains into ½ " chunks and put it in the bowl with the oil mixture.
Mix well till all the pieces are coated with oil.
Arrange the plantain pieces in the tray with the cut side facing up.
Bake for 15 minutes till they are slightly golden brown. Don't overcook them.
Remove the tray from the oven.
If you don't have a tostonera (a press) then you can use a glass or a small bowl to press the slices gently.
Press each piece down till the plantain pieces become a bit flat.
Brush them lightly with some oil.
Bake again for 20 minutes till they are light golden brown. Make sure half way you flip the tostones.
Remove the baked tostones from the oven. Allow them to cool for 2-3 minutes on a wire rack.
Serve immediately with mojo sauce or any sauce of your choice.