Investing in the stock market can be difficult. Nowadays, there’s so much information available to investors promoting things such as get-rich-quick schemes.

I’m blocking all that out. I invest in the market to build my wealth over time. I want top-quality businesses in my portfolio that I believe can perform strongly over a long stretch.

The stock market is vast, but I’ve put most of my energy into focusing on FTSE shares, which have gone on a tear this year. I like what I see with these two.

GSK

First is pharmaceutical giant GSK (LSE: GSK). The stock has taken full advantage of the market rally. It’s up 11.6% so far this year.

But with its share price sliding around 5% in the last week, I reckon now could be a time to swoop in and buy some shares. It trades on 15.1 times earnings. I see that as good value for a high-quality business.

GSK is on my list due to its defensive nature. Regardless of external issues such as a weak economy, people will always need access to medicine and treatments.

That’s not to say the stock is risk-free. For example, some market spectators have concerns about the firm’s drug pipeline. The company has underperformed compared to its peers recently. Furthermore, it’s facing further legal trouble surrounding heartburn drug Zantac, which sparked its fall recently.

But with it now having nearly 90 products in its R&D pipeline, it seems the firm is turning a corner. As such, analysts have its earnings growth rising from 3% this year to 10% and 11% in 2025 and 2026 respectively. Its 12-month price target is £19.51, which represents an 18.1% premium from its current price.

I like to target income. Therefore, its 3.6% yield, in line with the Footsie average, is also attractive.

Diageo

I also think one of the market’s best offerings right now is Diageo (LSE: DGE). Unlike GSK, its share price has faltered lately. It’s down 5.8% year to date. Diageo shares have lost 20.7% of their value in the last 12 months.

The spirit maker has struggled as consumers have cut back on splashing out on its premium brands in favour of cheaper alternatives given the current economic environment. Sales have been hit especially hard in the US, which is the company’s largest market.

But I still see an incredibly strong underlying business. The company owns high-quality names such as Guinness and Captain Morgan. In the years to come, I think demand for its products will steadily grow due to rising wealth in developing countries.

With its share price struggling, investors can now pick up Diageo shares trading on 19.2 times earnings. That’s above the Footsie average (11) but considerably lower than its historical average of around 24.

To go with that, the stock has a 3.1% yield. That may not seem enticing given some of the higher yields available on the Footsie. However, it has increased its payout for 37 years on the trot, which is an incredible record.