Place oven rack to middle position, and preheat to 375°F.
In a small bowl, whisk the olive oil with the minced garlic for 30 seconds.
3 tablespoons extra-virgin olive oil, 2 cloves garlic
Pour the olive oil/garlic mixture through a fine mesh sieve set over a large bowl. Press the garlic with a rubber spatula or the back of a wooden spoon to extract as much garlic oil as possible. Reserve the garlic for another use.
Microwave the butter, in a small bowl, at 30% power for 20-40 seconds. The butter could bubble over, so watch closely in the last 10 seconds. Add it to the olive oil/garlic mixture and stir well.
3 tablespoons unsalted butter
Add the salt, black pepper, and your favorite herbs/seasonings to the butter/oil mixture, then add the bread cubes. Toss until the cubes are evenly coated in the oil/butter mixture.
kosher salt, freshly ground black pepper, crushed red pepper**, 3 cups rustic bread or baguette*
Pour the croutons onto a rimmed baking sheet and bake 15-25 minutes, or until golden brown and crisp.
Remove from the oven***, sprinkle with the Parmesan cheese, and toss until all croutons are covered. Allow to cool completely.
4 tablespoons finely grated Parmesan cheese