In a small frying pan, heat the oil then add the mustard and fennel seeds and cook for a few minutes until they become fragrant and start to pop but don’t burn.
Set aside to cool.
Slice the cucumber and the radishes into thin discs and arrange on a platter.
Combine the cooled oil with red wine vinegar and season with rock salt to taste.
Drizzle the dressing over the cucumber and radish and then scatter with rocket.
Recipe by appetite magazine at https://www.appetitemag.co.uk/radish-and-cucumber-salad/