Your primary defenses against cross-contamination include proper planning in the order of what you're cutting and proper cleaning between uses. In the case of your stew, simply cut the vegetables first and then cut your meat. Doing so in this order you won't need to wash the board between the vegetables and meat. If you want to expedite the cooking process, then either use a separate board for the meat first so that you can start browning it while cutting the vegetables, or simply wash and re-use the board. A good scrubbing with hot soapy water is fine for your knife and board (including wood boards).
As mentioned previously, if you're still concerned about bacteria you can rub the board with lemon juice or vinegar which will kill any residual bacteria.
Using separate boards that are relegated to specific meat vs. vegetable duty isn't necessary as long as you're properly cleaning your boards. A board only used for meat items is just as liable to transfer bacteria to the next item being cut on it if it isn't properly washed between uses. That being said, if you're properly cleaning them then it's fine to cut vegetables on a board that's also been used previously for meat.
As for cutting boards, your best bet for the care and maintenance for your knives are either wood or composite materials (usually a laminated product of paper and resin - "Epicurean" being a prominent brand.
Never use a tempered glass cutting board or other hard surface (granite, marble, Corian, etc.) as these are heavily damaging to the edge of your blade and unsafe for you as there is nothing for the knife to bite and grip into and it's much more likely to slip and cut you.
Plastic cutting boards and mats aren't very good on your knives and the boards in particular are either too hard and dull your blade prematurely or are soft and end up with lots of cuts and grooves which then trap food. People often have a false sense of security with plastic boards believing them to be "non-porous". As the board is used, food material ends up crammed into the cuts and grooves and while the boards can go into the dishwasher, that only removes the surface grime, not that which is impacted and over time you increase the potential for bacterial growth to occur.
Wood boards (including bamboo) are much better on your knives but to maintain them in good condition you need to properly maintain them. Periodically, when they look dry (kind of like chapped skin) you need to oil them with mineral oil. The mineral oil you buy at your local drugstore or grocery store pharmacy is fine, no need to buy fancy "block oil" in gourmet shops. Don't use vegetable based oils as they will go rancid and transfer the flavor to your food. I like to give the cutting board a heavy coating at night, let it soak in overnight, and then buff off anything that didn't soak in. This will keep your wood fibers soft and supple so that the board won't split and crack, the fibers will swell back together making it more "self-healing" as you cut on it, and the oil in the wood will repel liquids that would otherwise try to soak in. When a wooden board gets marred and nicked up you just need to take it to the garage and give it a good sanding before dusting off, rinsing and re-oiling.
Don't use bleach on boards (plastic or otherwise) as it will typically leave a distinct smell in the board.
I give my coffee maker an internal cleanse with vinegar and water once a month to avoid scale build-up. I use 1/2 cup of white vinegar plus water to make a full pot, run that through my maker two or three times, and then run five or six pots of plain water through the maker until there is no longer any scent of the vinegar. I clean the pot and its basket and insert once a week in the dishwasher, and wipe down the case and heating element daily. I've been using the same drip coffee maker (with its glass, dishwasher-safe pot) for about five years.
On those occasions when I've run out of white vinegar, I use a tablespoon of citric acid dissolved in the first few cleaning pots of water, and then run five or six pots of plain water through the maker. Citric acid is just as effective as white vinegar for descaling but doesn't smell as strong; it's also inexpensive.
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When washing vegetables that can get muddy (Kale, leeks, etc.) I generally recommend first using tepid to slightly warm water to help soften the mud more easily. Leeks should be split down the middle and then can be fanned under warm water which will help wash the dirt out more readily.
For Kale, if it isn't muddy then you can use cold water and give it a soak and agitate as hobodave indicated below. If they're muddy and dirty, then I'd use slightly warmer water to first clean them and then give them a soak in some cold water to help plump them up and increase their turgor pressure to make them nice and crisp.
A good wash in water (universal solvent) should be enough. Most of what I've read on the effectiveness of "vegetable wash sprays" say that they're no better than a good wash with water.