Portfolios are built from the ground up. At the foundation you need strong, durable, resilient companies -- complementary businesses chosen for their superiority in industry, innovation, global presence, and domestic dominance. 

With more than 5,000 companies at your trading fingertips, selecting those to serve as the cornerstones of a well-rounded portfolio -- and not just an assemblage of random stocks -- can be daunting. So we've grabbed our hard hats and created a blueprint to help you break ground and build your investment dream house.

Here you'll find companies that Motley Fool writers and analysts deem strong enough to anchor a long-term-focused portfolio. These 10 companies (and a bonus ETF!) include:

  • A ubiquitous fast-food chain that's proving bulletproof in any economic environment.
  • A company that reinvented the entire home entertainment industry ... and is still at it.
  • Another that enhances your listening experience with sound technology that has become the standard in the electronics manufacturing field.
  • An expanding business tailor-made for heavy-metal fans -- that is, connoisseurs of iron, lead, steel, zinc, copper.

Looking for a few blue chips to round out your portfolio? Check. Tech, defense, energy, or financial services? Check, check, check, and check. And for set-it-and-forget-it or risk-averse investors, you'll find a bonus ETF recommendation from our resident Fool fund expert. 

These are the kinds of companies that we seek and tirelessly follow in our own Motley Fool Stock Advisor stock-picking service. (In fact, some of them are actual recommendations we have made to our members, which you'll see disclosed after each write-up.) And all are informed by some core beliefs that we hope will help guide you through your illustrious investing career:

1. Buy businesses, not stocks. Stocks are not just slips of paper (or, more likely nowadays, electronic confirmation notices). When we buy shares of stock we become part-owners of a living, breathing business. Charts, graphs, tea leaves, and that CNBC anchor's latest rant tell only a sliver of the story (if that). As bona-fide business owners we look at the people running our company, the customers, the competitors, and the long-term prospects to guide our investment decisions.

2. Buy to hold. No, that's not a typo. While buy "and" hold is a strategy to which we aspire, we're never so wed to any recommendation that we hold onto it just to hold. Businesses change. Strategies falter. Managements make bad calls. Game-changing events can render a once-beloved company completely obsolete. So while our intention is to invest in companies whose stock can be passed down to our grandkids' grandkids, when our original investment thesis no longer stands true -- or when a better opportunity arises -- we sell.

3. Timing is everything. But not in the way you might think. We don't "time the market." But we firmly believe that time -- a long-term investing time horizon measured in years (even decades) -- is what separates great investors from the pack. Having the temperament to stick to it and to give your stock market investments ample time to compound is one key to building real wealth. The other key to stick-to-itiveness is continuing to add to your investments over time. 

Before we regale you with our handpicked list of core stocks, we'd like to point out something that all of us have in common (you, The Motley Fool analysts making these recommendations, and even our entire company): We are all individual investors. And every single one of us starts at the very same place -- making that very first trade. So, without further ado, fellow investors, let's break ground and start building that portfolio. Each full write-up can be accessed by clicking on the company name:

Google and Microsoft are Motley Fool Inside Value picks. Google is a Motley Fool Rule Breakers selection. Dolby Laboratories and Netflix are Motley Fool Stock Advisor recommendations. Johnson & Johnson is a Motley Fool Income Investor recommendation. Motley Fool Options has recommended a diagonal call position on Johnson & Johnson. Motley Fool Options has recommended a diagonal call position on Microsoft. The Fool owns shares of Google, Johnson & Johnson, and Microsoft. True to its name, The Motley Fool is made up of a motley assortment of writers and analysts, each with a unique perspective; sometimes we agree, sometimes we disagree, but we all believe in the power of learning from each other through our Foolish community. The Motley Fool has a disclosure policy.