Step 1

Finely dice the onions and place them into a jar.

Step 2

Heat the water, vinegar, sugar, and salt in a saucepan, stirring to dissolve the sugar. When it starts boiling, pour it over the onion in the jar.

Step 3

Leave to pickle for 2-3 hours before using. Drain before use.

Step 4

Cut the butter into cubes and allow it to come to room temperature.

Step 5

Place the softened butter with the pickled onions and all other ingredients into a food processor and blend until smooth.

Step 6

Serve immediately, or place the chimichurri butter onto a piece of non-stick baking paper/parchment paper. Roll the compound butter into a log and twist the ends tightly to secure it.

Step 7

Place upright in the fridge and use within 5-6 days. Freeze for 3-4 months. Defrost in the refrigerator overnight.