Building a portfolio for long-term growth isn't about chasing the latest fads or trying to time the next big crash. It is about finding the best stocks and sticking with them through thick and thin.

Thankfully, Aussie investors have access to a range of ASX ETFs that make tapping into some of the best stocks in the world easier than ever.

But which ones could be great long term picks? Here are three that I would buy and hold:

Betashares Asia Technology Tigers ETF (ASX: ASIA)

When it comes to growth markets, Asia remains one of the most powerful and dynamic regions in the world. And it is not just about manufacturing anymore — Asia is now a leader in innovation, technology, and digital services.

The Betashares Asia Technology Tigers ETF offers investors a simple way to access the region's tech giants. It holds major names like Tencent, Alibaba, and Taiwan Semiconductor, companies that are at the forefront of cloud computing, e-commerce, artificial intelligence, and more.

Over the long term, rising incomes, growing middle classes, and rapid digital adoption across Asia should provide powerful tailwinds. This could make the Betashares Asia Technology Tigers ETF a great ASX ETF to buy and hold.

Betashares Global Cybersecurity ETF (ASX: HACK)

In an increasingly digital world, cybersecurity has moved from being a small concern to a necessity. Every year, cyber threats become more sophisticated — and governments, businesses, and individuals are spending more than ever to protect themselves.

That's where the Betashares Global Cybersecurity ETF comes in. This ASX ETF provides exposure to a diversified portfolio of global cybersecurity leaders like Palo Alto Networks, CrowdStrike, and Fortinet.

The cybersecurity sector is expected to grow strongly over the next decade as threats escalate and demand for digital protection surges. This bodes well for the companies held by this fund.

Betashares Nasdaq 100 ETF (ASX: NDQ)

If you're looking for an ASX ETF that captures the innovation heartbeat of the world, it is hard to go past the Betashares Nasdaq 100 ETF.

This fund gives you access to the 100 largest non-financial companies listed on the Nasdaq, including giants like Apple, Microsoft, Amazon, Tesla, NVIDIA, and Meta. These are companies leading the way in artificial intelligence, cloud computing, electric vehicles, and digital transformation.

While the Nasdaq can be more volatile than broader markets at times, history shows that over the long term, it has delivered some of the strongest returns of any major index.

For investors looking for buy and hold investments, this could be a fund to buy.