Heat a 12-inch skillet or Dutch oven over medium-high and add the olive oil.
Add the diced onion and sauté for about 5 minutes, stirring occasionally, until the onion begins to soften.
Add the minced garlic and cook for 1 minute, stirring so it does not brown.
Add the ground beef and cook, breaking it up with a spoon, until browned and no longer pink.
Stir in the Italian seasoning and black pepper until evenly distributed.
Add the broken lasagna noodles, pour in the diced tomatoes with their juice, the tomato sauce, and the water, stirring to combine so noodles are mostly submerged.
Cover the pan and simmer over medium-low heat for 20 to 25 minutes, stirring occasionally, until the noodles are tender and cooked through.
Taste and add salt as needed, adjusting seasoning with more pepper or Italian seasoning if desired; stir well.
Dollop the ricotta over the pasta in tablespoonfuls, distributing evenly, then gently stir a few times to incorporate without overmixing.
Reduce heat to low, arrange the mozzarella slices evenly over the top, cover, and cook 2 to 3 minutes until the cheese melts.
Sprinkle the torn basil over the lasagna, then serve immediately.
