The proven Zacks Rank system focuses on earnings estimates and estimate revisions to find winning stocks. Nevertheless, we know that our readers all have their own perspectives, so we are always looking at the latest trends in value, growth, and momentum to find strong picks.Considering these trends, value investing is clearly one of the most preferred ways to find strong stocks in any type of market. Value investors use a variety of methods, including tried-and-true valuation metrics, to find these stocks.Zacks has developed the innovative Style Scores system to highlight stocks with specific traits. For example, value investors will be interested in stocks with great grades in the "Value" category. When paired with a high Zacks Rank, "A" grades in the Value category are among the strongest value stocks on the market today.One company to watch right now is United Natural Foods (UNFI). UNFI is currently sporting a Zacks Rank of #1 (Strong Buy), as well as an A grade for Value. The stock is trading with a P/E ratio of 13.49, which compares to its industry's average of 17.60. Over the last 12 months, UNFI's Forward P/E has been as high as 15.89 and as low as 4.35, with a median of 9.68.We should also highlight that UNFI has a P/B ratio of 1.76. Investors use the P/B ratio to look at a stock's market value versus its book value, which is defined as total assets minus total liabilities. This company's current P/B looks solid when compared to its industry's average P/B of 2.15. Within the past 52 weeks, UNFI's P/B has been as high as 1.89 and as low as 0.68, with a median of 1.36.Finally, we should also recognize that UNFI has a P/CF ratio of 6.64. This data point considers a firm's operating cash flow and is frequently used to find companies that are undervalued when considering their solid cash outlook. UNFI's current P/CF looks attractive when compared to its industry's average P/CF of 18.33. Within the past 12 months, UNFI's P/CF has been as high as 7.13 and as low as 1, with a median of 2.36.These are only a few of the key metrics included in United Natural Foods's strong Value grade, but they help show that the stock is likely undervalued right now. When factoring in the strength of its earnings outlook, UNFI looks like an impressive value stock at the moment. Time to Invest in Legal Marijuana If you’re looking for big gains, there couldn’t be a better time to get in on a young industry primed to skyrocket from $17.7 billion back in 2019 to an expected $73.6 billion by 2027. After a clean sweep of 6 election referendums in 5 states, pot is now legal in 36 states plus D.C. Federal legalization is expected soon and that could be a still greater bonanza for investors. Even before the latest wave of legalization, Zacks Investment Research has recommended pot stocks that have shot up as high as +285.9%. You’re invited to check out Zacks’ Marijuana Moneymakers: An Investor’s Guide. It features a timely Watch List of pot stocks and ETFs with exceptional growth potential.Today, Download Marijuana Moneymakers FREE >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report United Natural Foods, Inc. (UNFI): Free Stock Analysis Report To read this article on Zacks.com click here.