Vegan mexican marrow tostadas

This is a recreation of a dish I recently had in Wahaca in Islington of crispy toasted mini tortillas topped with a spicy and fresh tomato salsa a generous squeeze of lime juice and a first for me cactus! They were so delicious I wanted to create something at home that was just as tasty but easier to make (these would also make incredibly good vegan canapes)...

You will need;
Tortillas (as many as you want to gobble)
Marrow, chopped into small cubes
1 tomato, diced
3 spring onions, finely slices
1 can refried beans
3 cloves garlic
1/2 green chilli

To garnish;
Juice of a lime
Your favourite chilli sauce (mine it smoked chipotle)

• If you want to make mini tostadas take a small cutter and cut out circles from the tortillas, if you want to make a larger version and have one per person then miss this step out.
• Lay your tortillas onto a baking tray and brush with a little olive oil and salt on each side, place a rack on top of them to stop them curling up and bake in a low temperature oven (100 C) for about 10 minutes until crisp then allow to cool. 
• Meanwhile fry your marrow in the chilli and garlic until golden and soft and heat your refried beans in a pan. 
• Finally assemble your tostadas by spreading a teaspoon of refried beans followed by a teaspoon of marrow then top with tomatoes and spring onions a splash of chilli sauce and a squeeze of lime. Munch!