Mexican corn croquettes

Name: Mexican corn croquettes
Prep time: 45 min
Total time: 45 min
Cuisine: Mexican, Latin American, American
Ingredients: 50 g Maizena cornflour; 60 g panko breadcrumbs; 2 garlic cloves; ¼ bunch coriander; 1 lime; 2 corn cobs; 1 onion; 1 tsp chilli flakes (e.g. Fine Food Chile Chipotle); 1 tsp ground coriander seeds; 1 tsp dried thyme; ¼ tsp garlic powder; 1 tsp salt; 2 pinches salt; 1 tbsp olive oil; oil , for deep-frying; 1 tbsp mayonnaise; 30 g butter; 1 fresh egg yolk; 100 g sour single cream; 100 g medium-fine polenta