Finely chop the onion, celery (if using) and garlic.
Heat the olive oil in a large saucepan over a medium heat.
Fry the onion, celery and garlic gently for about 5 minutes to soften.
While that's frying peel and chop the potato into small dice - about 1 cm or a bit smaller. The smaller you chop the quicker they cook!
Add the paprika to the onion mixture and stir and continue cooking for 1-2 minutes.
Add the chopped potato and flour and stir well for a minute or so.
Add the almond milk, bring to the boil and simmer for 10-15 minutes, until the cubes of potato are cooked.
Drain the sweetcorn, add to the chowder and bring back to the boil.
This step is optional but I like to take out about half the chowder at this point, blend it and add it back in. It's not essential because the flour thickens the chowder anyway but it makes it really creamy.
Season to taste with salt and black pepper and serve with a little sprinkle of paprika to garnish.