The S&P 500 has fallen 19% this year, which can make now an unnerving time to invest in the stock market. But with valuations coming down sharply, it's arguably the best time to load up on investments for the long haul, especially when you're talking about businesses that have plenty of room to grow and expand in the years ahead.

A couple of stocks that could be excellent options to buy and forget about today are Eli Lilly (LLY 3.77%) and Nvidia (NVDA 4.00%). Their businesses are sound financially, and they have promising futures.

1. Eli Lilly

Drugmaker Eli Lilly hasn't been doing badly this year as its shares are up 12%. And that shouldn't come as a big surprise since the business has been remained strong even amid slowdowns in the economy due to the pandemic and rising inflation. Its profit margin has generally been fairly strong at more than 22% of revenue over the past three years, as shown in the chart.

LLY Profit Margin (Quarterly) Chart

LLY Profit Margin (Quarterly) data by YCharts

Eli Lilly's margins dipped recently, but that was due to a rise in costs related to acquisitions, specifically, in-process research and development (IPR&D) and development milestones. Those expenses generally aren't recurring in nature, so investors would expect to see an improvement in the margin in future quarters.

Of key importance is that even with a $440 million charge of IPR&D for the period ended June 30 (which was 10 times more than the $42.8 million expense it incurred in the prior-year period), Eli Lilly still posted a solid profit of $952.5 million on revenue of $6.5 billion.

During this past quarter, the company had multiple products that generated more than $400 million in sales and grew at rates of more than 25%: Trulicity, Verzenio, and Jardiance. Plus, with a pipeline that features more than 40 trials that are in phase 2 or later, Eli Lilly isn't running out of growth opportunities anytime soon.

It has brought in nearly $5 billion in free cash flow over the trailing 12 months, which gives it ample room to support its growth. And at 1.3%, Eli Lilly also offers investors a modest dividend yield, which can help give you an added incentive to buy and hold this top healthcare stock for years.

2. Nvidia

Chipmaker Nvidia has been struggling this year with its shares crashing 55%. There have been many factors that have led to the bearishness of late, including supply chain issues, an inflated valuation, a slowdown in sales, and most recently, news that the U.S. government would be restricting the sale of certain chips to China and Russia.

The flurry of bad news has erased the tech stock's gains over the past few years, with Nvidia now trading at around its two-year lows. What's good about this reset, however, is that the business has become a much more tenable investment, trading at a valuation that's in line with where it was three years ago (with respect to earnings), as seen in the chart.

NVDA PE Ratio Chart

NVDA PE Ratio data by YCharts

There's definitely still room for the stock to go lower, but if you're buying for the long haul, this makes for a solid opportunity to buy Nvidia right now. According to Fortune Business Insights, the global semiconductor market will grow at a compound annual rate of 12.2% until 2029. And with Nvidia as an industry leader, it stands to benefit from many opportunities that will open up as industries become more digitized and connected to the internet.

Nvidia reported $6.3 billion in free cash flow over the trailing 12 months, and its profit totaled $7.7 billion on sales of $29.7 billion during that time (for a profit margin of 26%). The business may face challenges in the short term as the economy slows down, but over the long term, this still makes for a promising investment.

While it might be tempting to wait for more of a decline in the stock, given the tailspin that Nvidia's stock is on, odds are you'll still come out with some great gains if you buy it today and hang on for the long haul.