Grilled Flank Steak With Mango Chimichurri

For the Steak:

• 1.5 lbs. (680g) flank steak 
• ½ tsp. salt
• ½ tsp. pepper
• 1 onion, sliced 
• 1 tbsp. cumin 
• 1 tbsp. chilli powder 
• 2 limes, juiced 
• 1 tbsp. honey 
• 1 tbsp. red wine vinegar 
• 2 tbsp. olive oil 
• 2 cloves garlic, minced 
• 4 tbsp. cilantro, chopped 
• ½ tsp. red chilli flakes  

For the mango chimichurri: 

• 2 tsp. red wine vinegar 
• 4 tbsp. olive oil 
• ¼ tsp. red chilli flakes 
• 1 clove garlic, minced 
• ½ tsp. dried oregano 
• 4 tbsp. cilantro chopped 
• 1 mango, peeled, and cubed 
• ½ tsp. salt
• ¼ tsp. pepper