Mix together the flour, semolina, potato or corn starch, salt, baking powder and turmeric in a large bowl.
Add the oil and gradually whisk in the milk. Start with 500ml and add the extra 50ml only if needed. The batter should be like a thick pancake batter consistency. Beat it well until bubbles start to form.
Heat a large pan of water until boiling. Scoop some of the batter into a spaetzle press and press the spaetzle into the boiling water. If you have one like mine, scoop some of the batter onto the plate and use a scraper to scrape it into the water.
Once the spaetzle float to the top they are cooked. Skim them off using a slotted spoon and place in a colander. Rinse briefly with cold water and drain well. Repeat with the rest of the batter.
To make the cheese sauce, boil the potato, carrot and cashews until the vegetables are soft.
Drain well and place in a blender along with the stock cube, nutritional yeast, salt, mustard, lemon juice, garlic and onion powders, smoked paprika, olive oil and milk and blend until smooth.