Profitable businesses can be a great source of extra cash. However, building a portfolio that can generate significant passive income through a Stocks and Shares ISA takes time.

Therefore, the most essential thing that investors must look for is a company with mighty long-term prospects. I think there are a few that can give investors a great start.

Please note that tax treatment depends on each client’s individual situation and may change in the future. The content of this article is for informational purposes only. It is not intended to be and does not constitute any form of tax advice. Readers are responsible for conducting their own due diligence and obtaining professional advice before making any investment decisions.

Game workshops

I think investors starting from scratch right now could do very well considering the stock Game workshops (LSE:GAW). The company has a dividend yield of just over 3%.

This may not seem like much, but there is something essential to pay attention to. The point is that the company has a great track record of increasing shareholder payouts over the last few years.

Although the company has mighty intellectual property, Warhammer is not a product that people absolutely need. This means that in the event of an economic downturn, there is always a risk of lower profits.

Still, the company has shown impressive resilience in the past. And while this is not a guarantee of future success, I believe it is something investors should pay attention to.

Supermarket Income REIT

Another investment I think is worth exploring is Supermarket Income REIT (LSE:SUPR). The company is a real estate investment trust (REIT) that leases a portfolio of retail properties.

The company’s stock currently offers a dividend yield of 9%, allowing it to start returning enormous amounts of cash to investors right from the start. And existing leases still have an average long term.

A risk that investors must keep in mind is that more than 50% of the company’s revenue comes from two tenants. And that puts it in a tender position when it comes to negotiating future rent increases.

Importantly, Tesco has been increasing the number of stores since 2020. And this is a very positive development when it comes to long-term demand for Supermarket Income REIT properties.

Starting from scratch

Games Workshop delivers mighty growth and Supermarket Income REIT offers high initial yields. Together, I think they could create a mighty passive income portfolio.

Over the last five years, both companies have collectively achieved an average annual dividend enhance of 15%. If you add an average initial yield of 6% at today’s prices, the result looks engaging.

Investing £100 a month at this rate of return could build a portfolio generating over £1,500 in dividends a year after 10 years (although this is not guaranteed). In the long run, the equation looks even more attractive.

Continuing to invest at this rate for 20 years increases the return to £7,375 a year and £31,301 after 30 years. With a Stocks and Shares ISA, none of this has to be paid out as dividend tax.

Regular investing

I believe that starting from scratch you can earn over £7,000 a year in dividends by investing just £100 a month. And it doesn’t depend on whether you get lucky with just one share.

Games Workshop and Supermarket Income REIT are two stocks that I think could turn a blank ISA into a passive income machine.