I'm routinely adding more cash to my portfolio. On top of that, I don't automatically reinvest my dividends. As a result, cash is continually flowing into my portfolio, giving me more capital to invest.

However, I'm still pretty picky about where I allocate my limited capital. I focus new investments on my highest-conviction ideas. Brookfield Infrastructure Partners (BIP 2.21%) is at the top of that list right now. If I only had $100 to invest, I'd use it to buy a few more units of the leading global infrastructure operator.

Growth at a bargain price

Brookfield Infrastructure Partners recently reported strong first-quarter results. The company generated $554 million, or $0.72 per unit, of funds from operations (FFO). That was 12% above the prior year period. 

Brookfield Infrastructure expects to continue growing at a double-digit pace this year. The company is benefiting from elevated inflation levels as a result of its inflation-linked contracts. It's also seeing higher volumes across its transportation networks and the impact of new capital projects completed over the past year. The company recently finished its Heartland Petrochemical Complex in Canada, which should produce at capacity during the second half of this year. Finally, the company should continue to get a boost from the $2.4 billion of acquisitions it has closed in recent months. 

These catalysts have the company on track to grow its FFO per unit at a double-digit pace this year, pushing it up to around $3 per unit for the full year. With the company's price recently around $36.25 per unit, Brookfield Infrastructure trades at about 12 times its expected 2023 earnings.

That's an attractive price. The S&P 500 trades at 18.8 times forward earnings, while the Nasdaq 100 fetches 26.3 times forward earnings. Brookfield Infrastructure Partners is also cheaper than its economically equivalent corporate twin, Brookfield Infrastructure Corporation (BIPC 1.39%). With the corporate shares recently trading at around $46.50, that entity trades at 15.5 times earnings. 

More growth ahead

Brookfield Infrastructure is well-positioned to continue growing at a healthy rate. Inflation, global economic growth, and expansion projects should grow its FFO per unit at a 6% to 9% annual rate over the long term. Meanwhile, the company appears likely to deliver organic growth near the upper end of that range in the near term. Inflation remains elevated, and another sizable expansion project is coming online next year as semiconductor giant Intel finishes two fabrication plants Brookfield is helping finance. 

In addition, the company recently locked up two new acquisitions. It's investing $600 million to buy the European data center platform Data4. Meanwhile, it's participating in the privatization of Triton International. It's investing $1 billion in that deal, primarily funded by issuing over $900 million of Brookfield Infrastructure Corporation shares. 

The company expects to continue growing at a healthy pace for years to come, driven by the need for more infrastructure. CEO Sam Pollock wrote in the company's fourth-quarter letter to investors: "The infrastructure super-cycle is creating long-term investment opportunities that will require trillions of dollars. This is creating large-scale opportunities for well capitalized players that can invest in growing operating platforms or be a partner of choice for government and corporate entities that have less access to the capital markets." 

An attractive income stream

Those growth drivers will supply Brookfield Infrastructure with plenty of fuel to sustain and grow its attractive distribution. The company currently yields 4.2%. That's higher than the 3.3% dividend yield on the economically equivalent Brookfield Infrastructure Corporation solely because of the valuation disconnect between the two entities. It's also well above the 1.7% dividend yield of the S&P 500.

Brookfield Infrastructure expects to grow its distribution at a 5% to 9% annual rate in the future. The company has increased its payout for 14 straight years, including by 6% earlier this year. 

The complete package

Brookfield Infrastructure Partners offers a compelling growth profile and an attractive income stream at a low price. Meanwhile, it provides a lot of long-term upside to the global infrastructure megatrend. It's one of my highest-conviction investing ideas these days. It would be the top stock I'd buy if I only had $100 available to invest.