The U.S. stock market doubled between 2019 and 2021, putting high expectations on 2022 to be another above-average year. Yet there's concern that equity valuations have ballooned to unreasonably expensive levels. Long-term investors know that timing the market doesn't work. Rather, persevering even in the face of a potential market sell-off is the best option. As an example, if you had invested in the S&P 500 in October 2007 at its highest point right before the financial crisis, you still would have tripled your money between then and now. Investors interested in buying quality growth stocks in January should consider Adobe (NASDAQ: ADBE) and PayPal Holdings (NASDAQ: PYPL). Here's what makes each a great buy now. Image source: Getty Images. 1. Adobe: An anchor in infrastructure software When you think of big tech, you may think of companies like Apple, Microsoft, Alphabet, and Meta Platforms. Maybe even Nvidia or Tesla. Those businesses are certainty on a different level than others. However, right below that tier are sub $300 billion market cap businesses like Salesforce, Oracle, Intel, Intuit, and Shopify -- all well-known companies. It may surprise you to learn that Adobe is more valuable than any company on that "Tier 2" list, even though Adobe's stock price is down 25% from its all-time high. ADBE data by YCharts Adobe is the undisputed industry leader in digital media software for individuals, students, and businesses of all sizes. Adobe is also one of the pioneers of software as a service (SaaS). In 2013, Adobe converted its business from selling software that folks could download to a recurring revenue stream through Adobe Creative Cloud -- a subscription that grants access to the Adobe suite of products for a monthly or annual fee. Since then, Adobe has become one of the most stable software companies in the world. Its revenue growth may have slowed down, but its profit and free cash flow (FCF) are impeccable. ADBE Revenue (Annual) data by YCharts The above chart says it all. Over the past five years, Adobe has grown revenue by 116%, but its net income and FCF have both grown by over 150%. Although Adobe stock has increased nearly fourfold in the last five years, its price-to-earnings ratio and price-to-FCF ratio are right around the five-year median. ADBE Price to Free Cash Flow data by YCharts In short, Adobe is an incredibly entrenched business that generates subscription revenue, has moderate growth, and is converting more sales into actual profit. 2. Paypal: The future of finance PayPal and Adobe may be in completely different industries. But they are surprisingly similar stocks. Like Adobe, PayPal has come under fire for a slowing growth rate, but its profit and FCF have greatly improved compared to years past. PYPL Revenue (Annual) data by YCharts Also similar to Adobe, PayPal has crushed the market over the last five years, but PayPal stock is still priced around its five-year average valuation. PYPL PE Ratio data by YCharts PayPal is a great choice for investors interested in the financial sector, but not through a traditional bank like JPMorgan Chase. Rather, PayPal is a leader in peer-to-peer payments, supports small- and medium-sized businesses and the gig economy, and underpins e-commerce payment solutions. With a stock price own over 40% from its 52-week high and hovering around a 52-week low, PayPal is too strong of a business to ignore at this price. Two companies that are built to last Adobe and PayPal have strong fundamentals that can help each business power through tough economic cycles. While it's true that smaller, higher-risk growth stocks have more potential to produce outsized returns, Adobe and PayPal stand a better chance to grow steadily for decades to come. Adobe and PayPal could be ideal options for risk-averse investors looking for stable growth stocks to buy at a good price and hold over the long term. 10 stocks we like better than Adobe Inc.When our award-winning analyst team has a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.* They just revealed what they believe are the ten best stocks for investors to buy right now... and Adobe Inc. wasn't one of them! That's right -- they think these 10 stocks are even better buys. See the 10 stocks *Stock Advisor returns as of January 10, 2022 Suzanne Frey, an executive at Alphabet, is a member of The Motley Fool's board of directors. JPMorgan Chase is an advertising partner of The Ascent, a Motley Fool company. Teresa Kersten, an employee of LinkedIn, a Microsoft subsidiary, is a member of The Motley Fool's board of directors. Randi Zuckerberg, a former director of market development and spokeswoman for Facebook and sister to Meta Platforms CEO Mark Zuckerberg, is a member of The Motley Fool's board of directors. Daniel Foelber has the following options: long February 2022 $185 puts on Apple, long January 2022 $210 calls on PayPal Holdings, long January 2024 $200 calls on PayPal Holdings, long September 2022 $210 calls on PayPal Holdings, short February 2022 $180 puts on Apple, short January 2022 $220 calls on PayPal Holdings, and short January 2024 $210 calls on PayPal Holdings. The Motley Fool owns and recommends Alphabet (A shares), Alphabet (C shares), Apple, Intel, Intuit, Meta Platforms, Inc., Microsoft, Nvidia, PayPal Holdings, Salesforce.com, Shopify, and Tesla. The Motley Fool recommends Adobe Inc. and recommends the following options: long January 2022 $75 calls on PayPal Holdings, long January 2023 $1,140 calls on Shopify, long January 2023 $57.50 calls on Intel, long March 2023 $120 calls on Apple, short January 2023 $1,160 calls on Shopify, short January 2023 $57.50 puts on Intel, and short March 2023 $130 calls on Apple. The Motley Fool has a disclosure policy.Source