Warm the oil in a skillet. Add the entire garlic clove and thyme twigs and sizzle them for a minute.
Add the perch fillets to the skillet, season the upper side of the fillets, fry for a couple of minutes in high heat until golden.
Turn the fillets, add the cherry tomatoes, season them and fry them for a couple of minutes.
Make the caper mayo by adding all the ingredients in a bowl (grossly chop the capers in case you are using the big ones), mix well and season to taste.