In a small bowl, soak the saffron in the water. Set aside.
Cut the garlic bulb in half horizontally, drizzle it generously with olive oil and put it on a baking sheet to roast for about 15 minutes. Allow the garlic to cool enough to handle. Remove the garlic cloves from their shells - they should just fall out - and crush in a pestle and mortar.
Put the mayonnaise in a bowl and mix in the roasted garlic, saffron strands and their soaking water. Keep mixing until a thick sauce forms. The aioli can be stored in the fridge for 4-6 days.
Make the chorizo and corn fritters
In a frying pan on medium heat, cook the chorizo in a bit of oil. Set aside to cool.
In a medium bowl beat the eggs and half the milk.
In a large bowl, sift the flour and baking powder together. Whisk in the egg mixture. Gradually mix in the rest of the milk. Mix in the corn, melted butter, chorizo and spring onions. Season with salt and pepper, if using.
Heat a skillet on medium heat and add in a bit of oil. Drop the batter on the skillet by the spoonful, spacing them apart so that they do not run into each other. Fry for about 2 minutes on each side, until golden brown. Repeat with remaining batter, adding a bit of oil to the pan each time.