USA Adjusting Weighted Average in Inventory Valuation for increased costs

[jkenfield]

Hello! I am self taught and am wondering how to make accounting adjustment when the weighted average of cost of inventory has gone up dramatically. The value of my raw and finished good inventory had increased now that I have had to purchase materials at a higher price. My COGS is not accurate because the costs have now doubled on new products. Can I "reset" the average and apply the valuation change somewhere in my chart of accounts? And then how is this valuation change going to effect my profit and loss and balance sheet? How will it effect my taxes come reporting time? Any advice would be appreciated.