Beer Grain Mustard

300g Yellow Mustard Seeds
300g Black Mustard Seeds
300ml x Corona (1 with a mouthful taken out)
600 mls White Wine Vinegar
1.5 TBSP Caraway Seeds
1.5 TBSP Tarragon
1.5 TBSP Brown Sugar
0.5 TBSP Salt
0.5 TBSP Cracked black pepper