Preheat oven to 375 F. Line a baking sheet with aluminum foil. Slice plantain into 1-inch thick slices. Place on baking sheet & drizzle with olive oil. Sprinkle with salt.
Bake for 10 minutes. Remove from oven & with the end of a glass, ‘squash’ each piece down flat. Thinner = crispier. Place back in the oven for another 10 minutes or until crispy to your liking. Serve with guacamole.
In a small bowl, mash avocados. Add minced red onion, chopped sun-dried tomatoes, garlic powder, lemon juice, salt & pepper. Combine thoroughly & serve.
Just for interest, the special or tradional tool used to flatten plantain slices is called a ‘tostonera’.